Antimicrobial glass compositions, glasses and polymeric articles incorporating the same

ABSTRACT

Embodiments of the present invention pertain to antimicrobial glass compositions, glasses, and articles. The articles include a glass, which may include a glass phase and a cuprite phase. In other embodiments, the glasses include a plurality of Cu 1+  ions, a degradable phase including B 2 O 3 , P 2 O 5  and K 2 O, and a durable phase including SiO 2 . Other embodiments include glasses having a plurality of Cu 1+  ions disposed on the surface of the glass and in the glass network and/or the glass matrix. The article may also include a polymer. The glasses and articles disclosed herein exhibit a 2 log reduction or greater in a concentration of at least one of  Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa  bacteria, Methicillin Resistant  Staphylococcus aureus , and  E. coli , under the EPA Test Method for Efficacy of Copper Alloy as a Sanitizer testing condition and under Modified JIS Z 2801 for Bacteria testing conditions.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation and claims the benefit of priority under 35 U.S.C. § 120 of U.S. application Ser. No. 15/446,223, filed Mar. 1, 2017, which is a divisional of U.S. application Ser. No. 14/623,077, filed Feb. 16, 2015, which claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Application Ser. No. 62/034,842 filed on Aug. 8, 2014, U.S. Provisional Application Ser. No. 62/034,834, filed Aug. 8, 2014, U.S. Provisional Application Ser. No. 62/026,186 filed on Jul. 18, 2014, U.S. Provisional Application Ser. No. 62/026,177, filed Jul. 18, 2014, U.S. Provisional Application Ser. No. 61/992,987 filed on May 14, 2014, U.S. Provisional Application Ser. No. 61/992,980, filed May 14, 2014, U.S. Provisional Application Ser. No. 61/941,690 filed on Feb. 19, 2014, and U.S. Provisional Application Ser. No. 61/941,677, filed Feb. 19, 2014, the contents of which are relied upon and incorporated herein by reference in their entireties.

BACKGROUND

The present disclosure relates generally to antimicrobial glass compositions and articles incorporating such compositions. More particularly, the various embodiments described herein relate to glasses having antimicrobial attributes and articles that incorporate such glasses.

Consumer electronics articles, including touch-activated or touch-interactive devices, such as screen surfaces (e.g., surfaces of electronic devices having user-interactive capabilities that are activated by touching specific portions of the surfaces), have become increasingly more prevalent. As the extent to which the touch screen-based interactions between a user and a device increases, so too does the likelihood of the surface harboring microorganisms (e.g., bacteria, fungi, viruses, and the like) that can be transferred from user to user. Moreover, the housings which incorporate the touch-activated or touch-interactive devices also include surfaces that harbor such microorganisms that can be transferred from user to user. The concern of microorganism transfer is also a concern with equipment, furniture and architectural articles used in medical or office settings and many other articles in which users come into contact with surfaces.

To minimize the presence of microbes on various materials, so-called “antimicrobial” properties have been imparted to a variety of glasses; however, there is a need to provide entire articles (including the housing and any glasses used as cover glass) that also exhibit antimicrobial properties. Accordingly, antimicrobial articles useful for certain applications should be durable enough for the purpose for which they are used, while also providing continuous antimicrobial properties that are passive or do not require additional activation by a user or outside source (e.g., UV light). In addition, antimicrobial glasses and articles should provide controlled antimicrobial activity.

SUMMARY

A first aspect of the present disclosure pertains to an article that includes a carrier and a glass. Examples of suitable carriers include polymers, monomers, binders, solvents, and other materials used to form molded articles, formed articles, coatings on substrates or other such articles. Exemplary coatings may include anti-frictive coatings, coatings exhibiting a low coefficient of friction, or coatings that form a surface exhibiting a low coefficient of friction.

The glass of one or more embodiments may also include a composition that includes, in mole percent: SiO₂ in the range from about 40 to about 70, Al₂O₃ in the range from about 0 to about 20, a copper-containing oxide in the range from about 10 to about 50, CaO in the range from about 0 to about 15, MgO in the range from about 0 to about 15, P₂O₅ in the range from about 0 to about 25, B₂O₃ in the range from about 0 to about 25, K₂O in the range from about 0 to about 20, ZnO in the range from about 0 to about 5, Na₂O in the range from about 0 to about 20, and Fe₂O₃ in the range from about 0 to about 5. In some embodiments, the amount of copper-containing oxide is greater than the amount of Al₂O₃ (which may be about 5 mole percent or less, in some cases). In some instances, the composition may be free of Al₂O₃. Examples of suitable copper-containing oxides can include CuO, Cu₂O, or a combination thereof.

The article of one or more embodiments may include a plurality of Cu¹⁺ ions, Cu metal or a combination thereof. In some instances, the glass may be substantially free of tenorite.

The glass of one or more embodiments may include a cuprite phase and a glass phase. In some embodiments, the cuprite phase may include crystals that have an average major dimension of about 5 micrometers (μm) or less, or even about 1 micrometer (μm) or less.

A second aspect of the present disclosure pertains to an article that includes a carrier and a glass with a plurality of Cu¹⁺ ions, a degradable phase comprising at least one of B₂O₃, P₂O₅ and R₂O, and a durable phase comprising SiO₂. The glass may be formed from the compositions described herein. In some instances, the durable phase is present in an amount by weight that is greater than the degradable phase. The degradable phase of one or more embodiments leaches or is leachable in the presence of water.

The article may optionally include a cuprite phase, which may be dispersed in one or both of the degradable phase and the durable phase. The cuprite phase may have crystals having an average major dimension of about 5 micrometers (μm) or less, about 1 micrometer (μm) or less, or about 500 nanometers (nm) or less. The cuprite phase may comprise at least about 10 weight percent or at least about 20 weight percent of the glass.

In one or more embodiments, the glass includes a surface portion (having a depth of less than about 5 nanometers (nm)) that includes a plurality of copper ions. In some embodiments, at least 75% of the plurality of copper ions is Cu¹⁺. In other embodiments, less than about 25% of the plurality of copper ions is Cu²⁺.

A third aspect of the present disclosure pertains to an article including a carrier; and an inorganic material, wherein the inorganic material comprises a surface and a plurality of Cu¹⁺ ions disposed on the surface. The inorganic material may include a glass and may be formed form the compositions described herein. The inorganic material may be substantially free of tenorite.

In one or more embodiments, the plurality of Cu¹⁺ ions may be dispersed in a glass network and/or a glass matrix. In some instances, the glass network includes atoms to which the plurality of Cu¹⁺ ions is atomically bonded. The plurality of Cu¹⁺ ions may include cuprite crystals that are dispersed in the glass matrix.

The carrier may include a polymer, a monomer, a binder, a solvent, or combinations thereof. Carriers may include anti-frictive materials such as for example, fluorocarbons, fluorinated silanes, and alkyl perfluorocarbon silanes. The polymer used in the embodiments described herein can include organic or inorganic polymers. Exemplary polymers may include a thermoplastic polymer, a polyolefin, a cured polymer, an ultraviolet- or UV-cured polymer, a polymer emulsion, a solvent-based polymer, and combinations thereof. Specific examples of monomers include catalyst curable monomers, thermally-curable monomers, radiation-curable monomers and combinations thereof. The articles described herein may include a glass to carrier ratio in the range from about 10:90 to about 90:10, based on weight percent.

The glasses and articles described herein may exhibit a 2 log reduction or greater in a concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa bacteria, Methicillin Resistant Staphylococcus aureus, and E. coli, under the EPA Test Method for Efficacy of Copper Alloy as a Sanitizer testing conditions (herein, after the “EPA Test”).

The glasses and articles described herein according to one or more embodiments may exhibit a 4 log reduction or greater (e.g., 5 log reduction or greater) in a concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa bacteria, Methicillin Resistant Staphylococcus aureus, and E. coli, under JIS Z 2801 (2000) testing conditions. One or more embodiments of the glasses and articles described herein also exhibit a 4 log reduction or greater (e.g., 5 log reduction or greater) in a concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa, Methicillin Resistant Staphylococcus aureus, and E. coli, under modified JIS Z 2801 (2000) testing conditions (hereinafter, “Modified JIS Z 2801 Test for Bacteria”). The Modified JIS Z 2801 (2000) Test for Bacteria is described in greater detail herein.

In one or more embodiments, the glasses and articles described herein according to one or more embodiments may exhibit a 2 log reduction or greater (e.g., 4 log reduction or greater, or a 5 log reduction or greater) in a concentration of Murine Norovirus, under modified JIS Z 2801 (2000) testing conditions for evaluating viruses (hereinafter, “Modified JIS Z 2801 for Viruses”). The Modified JIS Z 2801 (2000) Test for Viruses is described in greater detail herein.

In some embodiments, the glasses and articles may exhibit the log reductions described herein (i.e., under the EPA Test, the JIS Z 2801 testing conditions, the Modified JIS Z 2801 Test for Bacteria and/or the Modified JIS Z 2801 Test for Viruses), for a period of one month or greater or for a period of three months or greater. The one month period or three month period may commence at or after the formation of the glass, or at or after combination of the glass with a carrier.

In one or more embodiments, the articles leach the copper ions when exposed or in contact with a leachate. In one or more embodiments, the articles leach only copper ions when exposed to leachates including water.

The articles described herein may form the housing for an electronic device.

A fourth aspect of the present disclosure pertains to a method of making an antimicrobial article. In one or more embodiments, the method includes melting a glass composition to form a glass comprising a plurality of Cu¹⁺ ions; and a glass phase, forming the glass into at least one of particulates and fibers, dispersing the at least one of particulates and fibers in a carrier, such as a polymer (as described herein), a monomer, or a binder, to provide a filled carrier and forming the filled carrier into the antimicrobial article. The glass composition may include the compositions described herein.

Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described herein, including the detailed description which follows, the claims, as well as the appended drawings.

It is to be understood that both the foregoing general description and the following detailed description are merely exemplary, and are intended to provide an overview or framework to understanding the nature and character of the claims. The accompanying drawings are included to provide a further understanding, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiment(s), and together with the description serve to explain principles and operation of the various embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of an antimicrobial glass in the form of a sheet according to one or more embodiments;

FIG. 2 is an enlarged partial view of the antimicrobial glass shown in FIG. 1.

FIG. 3 is a transmission electron microscopy (TEM) image of an antimicrobial glass, according to one or more embodiments;

FIG. 4 is a scanning electron microscopy (SEM) image of a cross-section of the antimicrobial glass shown in FIG. 3;

FIG. 5 is a SEM image of a fracture cross-section of the antimicrobial glass shown in FIG. 3;

FIG. 6 is an SEM image of the antimicrobial glass according to one or more embodiments;

FIG. 7A is a SEM-energy-dispersive X-ray spectroscopy (EDX) hypermap of a cross-section of Example 30, after being annealed overnight at 650° C. after melting at 1650° C.;

FIG. 7B is a SEM-EDX hypermap of a cross-section of Example 30 after being quenched in water after melting at 1650° C.;

FIG. 8A shows a fracture cross-section of Example 30, after an additional heat treatment at 800° C. for 1 hour;

FIG. 8B shows a polished cross-section of Example 30, after an additional heat treatment at 800° C. for 1 hour;

FIG. 9 illustrates the antimicrobial activity of glasses according to one or more embodiments;

FIG. 10 is a graph showing the antimicrobial activity of an antimicrobial glass described herein, when formed into particles and combined with a polymer carrier, after various time periods;

FIG. 11 is a graph illustrating the antimicrobial activity of various articles, according one or more embodiments;

FIG. 12 is a graph illustrating the antimicrobial activity of various articles, according to one or more embodiments;

FIG. 13 is a graph illustrating the antimicrobial activity of glasses having different amounts of copper;

FIG. 14 shows images of injection molded articles made from Example 12 and a polymer; and

FIG. 15 shows the antimicrobial activity of injection molded articles, according to one or more embodiments, with and without different surface treatments.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiment(s), examples of which are illustrated in the accompanying drawings.

A first aspect of the present disclosure pertains to antimicrobial glass compositions and glasses made from or including such compositions. The antimicrobial properties of the glasses disclosed herein include antiviral and/or antibacterial properties. As used herein the term “antimicrobial,” means a material, or a surface of a material that will kill or inhibit the growth of bacteria, viruses and/or fungi. The term as used herein does not mean the material or the surface of the material will kill or inhibit the growth of all species microbes within such families, but that it will kill or inhibit the growth or one or more species of microbes from such families.

As used herein the term “log reduction” means−log (C_(a)/C₀), where C_(a)=the colony form unit (CFU) number of the antimicrobial surface and C₀=the colony form unit (CFU) of the control surface that is not an antimicrobial surface. As an example, a 3 log reduction equals about 99.9% of the bacteria, viruses and/or fungi killed and a Log Reduction of 5=99.999% of bacteria, viruses and/or fungi killed.

In one or more embodiments, the antimicrobial glasses include a Cu species. In one or more alternative embodiments, the Cu species may include Cu¹⁺, Cu⁰, and/or Cu²⁺. The combined total of the Cu species may be about 10 wt % or more. However, as will be discussed in more detail below, the amount of Cu¹⁺ is minimized or is reduced such that the antimicrobial glass is substantially free of Cu²⁺. The Cu¹⁺ ions may be present on or in the surface and/or the bulk of the antimicrobial glass. In some embodiments, the Cu¹⁺ ions are present in the glass network and/or the glass matrix of the antimicrobial glass. Where the Cu¹⁺ ions are present in the glass network, the Cu¹⁺ ions are atomically bonded to the atoms in the glass network. Where the Cu¹⁺ ions are present in the glass matrix, the Cu¹⁺ ions may be present in the form of Cu¹⁺ crystals that are dispersed in the glass matrix. In some embodiments the Cu¹⁺ crystals include cuprite (Cu₂O). In such embodiments, where Cu¹⁺ crystals are present, the material may be referred to as an antimicrobial glass ceramic, which is intended to refer to a specific type of glass with crystals that may or may not be subjected to a traditional ceramming process by which one or more crystalline phases are introduced and/or generated in the glass. Where the Cu¹⁺ ions are present in a non-crystalline form, the material may be referred to as an antimicrobial glass. In some embodiments, both Cu¹⁺ crystals and Cu¹⁺ ions not associated with a crystal are present in the antimicrobial glasses described herein.

In one or more embodiments, the antimicrobial glass may be formed from a composition that can include, in mole percent, SiO₂ in the range from about 40 to about 70, Al₂O₃ in the range from about 0 to about 20, a copper-containing oxide in the range from about 10 to about 30, CaO in the range from about 0 to about 15, MgO in the range from about 0 to about 15, P₂O₅ in the range from about 0 to about 25, B₂O₃ in the range from about 0 to about 25, K₂O in the range from about 0 to about 20, ZnO in the range from about 0 to about 5, Na₂O in the range from about 0 to about 20, and/or Fe₂O₃ in the range from about 0 to about 5. In such embodiments, the amount of the copper-containing oxide is greater than the amount of Al₂O₃. In some embodiments, the composition may include a content of R₂O, where R may include K, Na, Li, Rb, Cs and combinations thereof.

In the embodiments of the compositions described herein, SiO₂ serves as the primary glass-forming oxide. The amount of SiO₂ present in a composition should be enough to provide glasses that exhibit the requisite chemical durability suitable for its use or application (e.g., touch applications, article housing etc.). The upper limit of SiO₂ may be selected to control the melting temperature of the compositions described herein. For example, excess SiO₂ could drive the melting temperature at 200 poise to high temperatures at which defects such as fining bubbles may appear or be generated during processing and in the resulting glass. Furthermore, compared to most oxides, SiO₂ decreases the compressive stress created by an ion exchange process of the resulting glass. In other words, glass formed from compositions with excess SiO₂ may not be ion-exchangeable to the same degree as glass formed from compositions without excess SiO₂. Additionally or alternatively, SiO₂ present in the compositions according to one or more embodiments could increase the plastic deformation prior break properties of the resulting glass. An increased SiO₂ content in the glass formed from the compositions described herein may also increase the indentation fracture threshold of the glass.

In one or more embodiments, the composition includes SiO₂ in an amount, in mole percent, in the range from about 40 to about 70, from about 40 to about 69, from about 40 to about 68, from about 40 to about 67, from about 40 to about 66, from about 40 to about 65, from about 40 to about 64, from about 40 to about 63, from about 40 to about 62, from about 40 to about 61, from about 40 to about 60, from about 41 to about 70, from about 42 to about 70, from about 43 to about 70, from about 44 to about 70, from about 45 to about 70, from about 46 to about 70, from about 47 to about 70, from about 48 to about 70, from about 49 to about 70, from about 50 to about 70, from about 41 to about 69, from about 42 to about 68, from about 43 to about 67 from, about 44 to about 66, from about 45 to about 65, from about 46 to about 64, from about 47 to about 63, from about 48 to about 62, from about 49 to about 61, from about 50 to about 60 and all ranges and sub-ranges therebetween.

In one or more embodiments, the composition includes Al₂O₃ an amount, in mole percent, in the range from about 0 to about 20, from about 0 to about 19, from about 0 to about 18, from about 0 to about 17, from about 0 to about 16, from about 0 to about 15, from about 0 to about 14, from about 0 to about 13, from about 0 to about 12, from about 0 to about 11, from about 0 to about 10, from about 0 to about 9, from about 0 to about 8, from about 0 to about 7, from about 0 to about 6, from about 0 to about 5, from about 0 to about 4, from about 0 to about 3, from about 0 to about 2, from about 0 to about 1, from about 0.1 to about 1, from about 0.2 to about 1, from about 0.3 to about 1 from about 0.4 to about 1, from about 0.5 to about 1, from about 0 to about 0.5, from about 0 to about 0.4, from about 0 to about 0.3, from about 0 to about 0.2, from about 0 to about 0.1 and all ranges and sub-ranges therebetween. In some embodiments, the composition is substantially free of Al₂O₃. As used herein, the phrase “substantially free” with respect to the components of the composition and/or resulting glass means that the component is not actively or intentionally added to the compositions during initial batching or subsequent post processing (e.g., ion exchange process), but may be present as an impurity. For example, a composition, a glass may be describe as being substantially free of a component, when the component is present in an amount of less than about 0.01 mol %.

The amount of Al₂O₃ may be adjusted to serve as a glass-forming oxide and/or to control the viscosity of molten compositions. Without being bound by theory, it is believed that when the concentration of alkali oxide (R₂O) in a composition is equal to or greater than the concentration of Al₂O₃, the aluminum ions are found in tetrahedral coordination with the alkali ions acting as charge-balancers. This tetrahedral coordination greatly enhances various post-processing (e.g., ion exchange process) of glasses formed from such compositions. Divalent cation oxides (RO) can also charge balance tetrahedral aluminum to various extents. While elements such as calcium, zinc, strontium, and barium behave equivalently to two alkali ions, the high field strength of magnesium ions causes them to not fully charge balance aluminum in tetrahedral coordination, resulting in the formation of five- and six-fold coordinated aluminum. Generally, Al₂O₃ can play an important role in ion-exchangeable compositions and strengthened glasses since it enables a strong network backbone (i.e., high strain point) while allowing for the relatively fast diffusivity of alkali ions. However, when the concentration of Al₂O₃ is too high, the composition may exhibit lower liquidus viscosity and, thus, Al₂O₃ concentration may be controlled within a reasonable range. Moreover, as will be discussed in more detail below, excess Al₂O₃ has been found to promote the formation of Cu¹⁺ ions, instead of the desired Cu¹⁺ ions.

In one or more embodiments, the composition includes a copper-containing oxide in an amount, in mole percent, in the range from about 10 to about 50, from about 10 to about 49, from about 10 to about 48, from about 10 to about 47, from about 10 to about 46, from about 10 to about 45, from about 10 to about 44, from about 10 to about 43, from about 10 to about 42, from about 10 to about 41, from about 10 to about 40, from about 10 to about 39, from about 10 to about 38, from about 10 to about 37, from about 10 to about 36, from about 10 to about 35, from about 10 to about 34, from about 10 to about 33, from about 10 to about 32, from about 10 to about 31, from about 10 to about 30, from about 10 to about 29, from about 10 to about 28, from about 10 to about 27, from about 10 to about 26, from about 10 to about 25, from about 10 to about 24, from about 10 to about 23, from about 10 to about 22, from about 10 to about 21, from about 10 to about 20, from about 11 to about 50, from about 12 to about 50, from about 13 to about 50, from about 14 to about 50, from about 15 to about 50, from about 16 to about 50, from about 17 to about 50, from about 18 to about 50, from about 19 to about 50, from about 20 to about 50, from about 10 to about 30, from about 11 to about 29, from about 12 to about 28, from about 13 to about 27, from about 14 to about 26, from about 15 to about 25, from about 16 to about 24, from about 17 to about 23, from about 18 to about 22, from about 19 to about 21 and all ranges and sub-ranges therebetween. In one or more specific embodiments, the copper-containing oxide may be present in the composition in an amount of about 20 mole percent, about 25 mole percent, about 30 mole percent or about 35 mole percent. The copper-containing oxide may include CuO, Cu₂O and/or combinations thereof.

The copper-containing oxides in the composition form the Cu¹⁺ ions present in the resulting glass. Copper may be present in the composition and/or the glasses including the composition in various forms including Cu⁰, Cu¹⁺ and Cu²⁺. Copper in the Cu⁰ or Cu¹⁺ forms provide antimicrobial activity. However forming and maintaining these states of antimicrobial copper are difficult and often, in known compositions, Cu¹⁺ ions are formed instead of the desired Cu⁰ or Cu¹⁺ ions.

In one or more embodiments, the amount of copper-containing oxide is greater than the amount of Al₂O₃ in the composition. Without being bound by theory it is believed that an about equal amount of copper-containing oxides and Al₂O₃ in the composition results in the formation of tenorite (CuO) instead of cuprite (Cu₂O). The presence of tenorite decreases the amount of Cu¹⁺ in favor of Cu¹⁺ and thus leads to reduced antimicrobial activity. Moreover, when the amount of copper-containing oxides is about equal to the amount of Al₂O₃, aluminum prefers to be in a four-fold coordination and the copper in the composition and resulting glass remains in the Cu¹⁺ form so that the charge remains balanced. Where the amount of copper-containing oxide exceeds the amount of Al₂O₃, then it is believed that at least a portion of the copper is free to remain in the Cu¹⁺ state, instead of the Cu¹⁺ state, and thus the presence of Cu¹⁺ ions increases.

The composition of one or more embodiments includes P₂O₅ in an amount, in mole percent, in the range from about 0 to about 25, from about 0 to about 22, from about 0 to about 20, from about 0 to about 18, from about 0 to about 16, from about 0 to about 15, from about 0 to about 14, from about 0 to about 13, from about 0 to about 12, from about 0 to about 11, from about 0 to about 10, from about 0 to about 9, from about 0 to about 8, from about 0 to about 7, from about 0 to about 6, from about 0 to about 5, from about 0 to about 4, from about 0 to about 3, from about 0 to about 2, from about 0 to about 1, from about 0.1 to about 1, from about 0.2 to about 1, from about 0.3 to about 1 from about 0.4 to about 1 from about 0.5 to about 1, from about 0 to about 0.5, from about 0 to about 0.4, from about 0 to about 0.3 from about 0 to about 0.2, from about 0 to about 0.1 and all ranges and sub-ranges therebetween. In some embodiments, the composition includes about 10 mole percent or about 5 mole percent P₂O₅ or, alternatively, may be substantially free of P₂O₅.

In one or more embodiments, P₂O₅ forms at least part of a less durable phase or a degradable phase in the glass. The relationship between the degradable phase(s) of the glass and antimicrobial activity is discussed in greater detail herein. In one or more embodiments, the amount of P₂O₅ may be adjusted to control crystallization of the composition and/or glass during forming. For example, when the amount of P₂O₅ is limited to about 5 mol % or less or even 10 mol % or less, crystallization may be minimized or controlled to be uniform. However, in some embodiments, the amount or uniformity of crystallization of the composition and/or glass may not be of concern and thus, the amount of P₂O₅ utilized in the composition may be greater than 10 mol %.

In one or more embodiments, the amount of P₂O₅ in the composition may be adjusted based on the desired damage resistance of the glass, despite the tendency for P₂O₅ to form a less durable phase or a degradable phase in the glass. Without being bound by theory, P₂O₅ can decrease the melting viscosity relative to SiO₂. In some instances, P₂O₅ is believed to help to suppress zircon breakdown viscosity (i.e., the viscosity at which zircon breaks down to form ZrO₂) and may be more effective in this regard than SiO₂. When glass is to be chemically strengthened via an ion exchange process, P₂O₅ can improve the diffusivity and decrease ion exchange times, when compared to other components that are sometimes characterized as network formers (e.g., SiO₂ and/or B₂O₃).

The composition of one or more embodiments includes B₂O₃ in an amount, in mole percent, in the range from about 0 to about 25, from about 0 to about 22, from about 0 to about 20, from about 0 to about 18, from about 0 to about 16, from about 0 to about 15, from about 0 to about 14, from about 0 to about 13, from about 0 to about 12, from about 0 to about 11, from about 0 to about 10, from about 0 to about 9, from about 0 to about 8, from about 0 to about 7, from about 0 to about 6, from about 0 to about 5, from about 0 to about 4, from about 0 to about 3, from about 0 to about 2, from about 0 to about 1, from about 0.1 to about 1, from about 0.2 to about 1, from about 0.3 to about 1 from about 0.4 to about 1, from about 0.5 to about 1, from about 0 to about 0.5, from about 0 to about 0.4, from about 0 to about 0.3 from about 0 to about 0.2, from about 0 to about 0.1 and all ranges and sub-ranges therebetween. In some embodiments, the composition includes a non-zero amount of B₂O₃, which may be, for example, about 10 mole percent or about 5 mole percent. The composition of some embodiments may be substantially free of B₂O₃.

In one or more embodiments, B₂O₃ forms a less durable phase or a degradable phase in the glass formed form the composition. The relationship between the degradable phase(s) of the glass and antimicrobial activity is discussed in greater detail herein. Without being bound by theory, it is believed the inclusion of B₂O₃ in compositions imparts damage resistance in glasses incorporating such compositions, despite the tendency for B₂O₃ to form a less durable phase or a degradable phase in the glass. The composition of one or more embodiments includes one or more alkali oxides (R₂O) (e.g., Li₂O, Na₂O, K₂O, Rb₂O and/or Cs₂O). In some embodiments, the alkali oxides modify the melting temperature and/or liquidus temperatures of such compositions. In one or more embodiments, the amount of alkali oxides may be adjusted to provide a composition exhibiting a low melting temperature and/or a low liquidus temperature. Without being bound by theory, the addition of alkali oxide(s) may increase the coefficient of thermal expansion (CTE) and/or lower the chemical durability of the antimicrobial glasses that include such compositions. In some cases these attributes may be altered dramatically by the addition of alkali oxide(s).

In some embodiments, the antimicrobial glasses disclosed herein may be chemically strengthened via an ion exchange process in which the presence of a small amount of alkali oxide (such as Li₂O and Na₂O) is required to facilitate ion exchange with larger alkali ions (e.g., K⁺), for example exchanging smaller alkali ions from an antimicrobial glass with larger alkali ions from a molten salt bath containing such larger alkali ions. Three types of ion exchange can generally be carried out. One such ion exchange includes a Na⁺-for-Li⁺ exchange, which results in a deep depth of layer but low compressive stress. Another such ion exchange includes a K⁺ for-Li⁺ exchange, which results in a small depth of layer but a relatively large compressive stress. A third such ion exchange includes a K⁺ for-Na⁺-exchange, which results in intermediate depth of layer and compressive stress. A sufficiently high concentration of the small alkali oxide in compositions may be necessary to produce a large compressive stress in the antimicrobial glass including such compositions, since compressive stress is proportional to the number of alkali ions that are exchanged out of the antimicrobial glass.

In one or more embodiments, the composition includes K₂O in an amount in the range from about 0 to about 20, from about 0 to about 18, from about 0 to about 16, from about 0 to about 15, from about 0 to about 14, from about 0 to about 13, from about 0 to about 12, from about 0 to about 11, from about 0 to about 10, from about 0 to about 9, from about 0 to about 8, from about 0 to about 7, from about 0 to about 6, from about 0 to about 5, from about 0 to about 4, from about 0 to about 3, from about 0 to about 2, from about 0 to about 1, from about 0.1 to about 1, from about 0.2 to about 1, from about 0.3 to about 1 from about 0.4 to about 1, from about 0.5 to about 1, from about 0 to about 0.5, from about 0 to about 0.4, from about 0 to about 0.3, from about 0 to about 0.2, from about 0 to about 0.1 and all ranges and sub-ranges therebetween. In some embodiments, the composition includes a non-zero amount of K₂O or, alternatively, the composition may be substantially free, as defined herein, of K₂O. In addition to facilitating ion exchange, where applicable, in one or more embodiments, K₂O can also form a less durable phase or a degradable phase in the glass formed form the composition. The relationship between the degradable phase(s) of the glass and antimicrobial activity is discussed in greater detail herein.

In one or more embodiments, the composition includes Na₂O in an amount in the range from about 0 to about 20, from about 0 to about 18, from about 0 to about 16, from about 0 to about 15, from about 0 to about 14, from about 0 to about 13, from about 0 to about 12, from about 0 to about 11, from about 0 to about 10, from about 0 to about 9, from about 0 to about 8, from about 0 to about 7, from about 0 to about 6, from about 0 to about 5, from about 0 to about 4, from about 0 to about 3, from about 0 to about 2, from about 0 to about 1, from about 0.1 to about 1, from about 0.2 to about 1, from about 0.3 to about 1, from about 0.4 to about 1, from about 0.5 to about 1, from about 0 to about 0.5, from about 0 to about 0.4, from about 0 to about 0.3, from about 0 to about 0.2, from about 0 to about 0.1 and all ranges and sub-ranges therebetween. In some embodiments, the composition includes a non-zero amount of Na₂O or, alternatively, the composition may be substantially free, as defined herein, of Na₂O.

In one or more embodiments, the composition may include one or more divalent cation oxides, such as alkaline earth oxides and/or ZnO. Such divalent cation oxides may be included to improve the melting behavior of the compositions. With respect to ion exchange performance, the presence of divalent cations can act to decrease alkali mobility and thus, when larger divalent cation oxides are utilized, there may be a negative effect on ion exchange performance. Furthermore, smaller divalent cation oxides generally help the compressive stress developed in an ion-exchanged glass more than the larger divalent cation oxides. Hence, divalent cation oxides such as MgO and ZnO can offer advantages with respect to improved stress relaxation, while minimizing the adverse effects on alkali diffusivity.

In one or more embodiments, the composition includes CaO in an amount, in mole percent, in the range from about 0 to about 15, from about 0 to about 14, from about 0 to about 13, from about 0 to about 12, from about 0 to about 11, from about 0 to about 10, from about 0 to about 9, from about 0 to about 8, from about 0 to about 7, from about 0 to about 6, from about 0 to about 5, from about 0 to about 4, from about 0 to about 3, from about 0 to about 2, from about 0 to about 1, from about 0.1 to about 1, from about 0.2 to about 1, from about 0.3 to about 1, from about 0.4 to about 1, from about 0.5 to about 1, from about 0 to about 0.5, from about 0 to about 0.4, from about 0 to about 0.3 from about 0 to about 0.2, from about 0 to about 0.1 and all ranges and sub-ranges therebetween. In some embodiments, the composition is substantially free of CaO.

In one or more embodiments, the composition includes MgO in an amount, in mole percent, in the range from about 0 to about 15, from about 0 to about 14, from about 0 to about 13, from about 0 to about 12, from about 0 to about 11, from about 0 to about 10, from about 0 to about 9, from about 0 to about 8, from about 0 to about 7, from about 0 to about 6, from about 0 to about 5, from about 0 to about 4, from about 0 to about 3, from about 0 to about 2, from about 0 to about 1, from about 0.1 to about 1, from about 0.2 to about 1, from about 0.3 to about 1, from about 0.4 to about 1, from about 0.5 to about 1, from about 0 to about 0.5, from about 0 to about 0.4, from about 0 to about 0.3, from about 0 to about 0.2, from about 0 to about 0.1 and all ranges and sub-ranges therebetween. In some embodiments, the composition is substantially free of MgO.

The composition of one or more embodiments may include ZnO in an amount, in mole percent, in the range from about 0 to about 5, from about 0 to about 4, from about 0 to about 3, from about 0 to about 2, from about 0 to about 1, from about 0.1 to about 1, from about 0.2 to about 1, from about 0.3 to about 1 from about 0.4 to about 1, from about 0.5 to about 1, from about 0 to about 0.5, from about 0 to about 0.4, from about 0 to about 0.3, from about 0 to about 0.2, from about 0 to about 0.1 and all ranges and sub-ranges therebetween. In some embodiments, the composition is substantially free of ZnO.

The composition of one or more embodiments may include Fe₂O₃, in mole percent, in the range from about 0 to about 5, from about 0 to about 4, from about 0 to about 3, from about 0 to about 2, from about 0 to about 1, from about 0.1 to about 1, from about 0.2 to about 1, from about 0.3 to about 1, from about 0.4 to about 1, from about 0.5 to about 1, from about 0 to about 0.5, from about 0 to about 0.4, from about 0 to about 0.3, from about 0 to about 0.2, from about 0 to about 0.1 and all ranges and sub-ranges therebetween. In some embodiments, the composition is substantially free of Fe₂O₃.

In one or more embodiments, the composition may include one or more colorants. Examples of such colorants include NiO, TiO₂, Fe₂O₃, Cr₂O₃, Co₃O₄ and other known colorants. In some embodiments, the one or more colorants may be present in an amount in the range up to about 10 mol %. In some instances, the one or more colorants may be present in an amount in the range from about 0.01 mol % to about 10 mol %, from about 1 mol % to about 10 mol %, from about 2 mol % to about 10 mol %, from about 5 mol % to about 10 mol %, from about 0.01 mol % to about 8 mol %, or from about 0.01 mol % to about 5 mol %.

In one or more embodiments, the composition may include one or more nucleating agents. Exemplary nucleating agents include TiO₂, ZrO₂ and other known nucleating agents in the art. The composition can include one or more different nucleating agents. The nucleating agent content of the composition may be in the range from about 0.01 mol % to about 1 mol %. In some instances, the nucleating agent content may be in the range from about 0.01 mol % to about 0.9 mol %, from about 0.01 mol % to about 0.8 mol %, from about 0.01 mol % to about 0.7 mol %, from about 0.01 mol % to about 0.6 mol %, from about 0.01 mol % to about 0.5 mol %, from about 0.05 mol % to about 1 mol %, from about 0.1 mol % to about 1 mol %, from about 0.2 mol % to about 1 mol %, from about 0.3 mol % to about 1 mol %, or from about 0.4 mol % to about 1 mol %, and all ranges and sub-ranges therebetween.

The glasses formed from the compositions may include a plurality of Cu¹⁺ ions. In some embodiments, such Cu¹⁺ ions form part of the glass network and may be characterized as a glass modifier. Without being bound by theory, where Cu¹⁺ ions are part of the glass network, it is believed that during typical glass formation processes, the cooling step of the molten glass occurs too rapidly to allow crystallization of the copper-containing oxide (e.g., CuO and/or Cu₂O). Thus the Cu¹⁺ remains in an amorphous state and becomes part of the glass network. In some cases, the total amount of Cu¹⁺ ions, whether they are in a crystalline phase or in the glass matrix, may be even higher, such as up to 40 mol %, up to 50 mol %, or up to 60 mol %.

In one or more embodiments, the glasses formed form the compositions disclosed herein include Cu¹⁺ ions that are dispersed in the glass matrix as Cu¹⁺ crystals. In one or more embodiments, the Cu¹⁺ crystals may be present in the form of cuprite. The cuprite present in the glass may form a phase that is distinct from the glass matrix or glass phase. In other embodiments, the cuprite may form part of or may be associated with one or more glasses phases (e.g., the durable phase described herein). The Cu¹⁺ crystals may have an average major dimension of about 5 micrometers (μm) or less, 4 micrometers (μm) or less, 3 micrometers (μm) or less, 2 micrometers (μm) or less, about 1.9 micrometers (μm) or less, about 1.8 micrometers (μm) or less, about 1.7 micrometers (μm) or less, about 1.6 micrometers (μm) or less, about 1.5 micrometers (μm) or less, about 1.4 micrometers (μm) or less, about 1.3 micrometers (μm) or less, about 1.2 micrometers (μm) or less, about 1.1 micrometers or less, 1 micrometers or less, about 0.9 micrometers (μm) or less, about 0.8 micrometers (μm) or less, about 0.7 micrometers (μm) or less, about 0.6 micrometers (μm) or less, about 0.5 micrometers (μm) or less, about 0.4 micrometers (μm) or less, about 0.3 micrometers (μm) or less, about 0.2 micrometers (μm) or less, about 0.1 micrometers (μm) or less, about 0.05 micrometers (μm) or less, and all ranges and sub-ranges therebetween. As used herein and with respect to the phrase “average major dimension”, the word “average” refers to a mean value and the word “major dimension” is the greatest dimension of the particle as measured by SEM. In some embodiments, the cuprite phase may be present in the antimicrobial glass in an amount of at least about 10 wt %, at least about 15 wt %, at least about 20 wt %, at least about 25 wt % and all ranges and subranges therebetween of the antimicrobial glass.

In some embodiments, the glasses may include about 70 wt % Cu¹⁺ or more and about 30 wt % of Cu²⁺ or less. The Cu²⁺ ions may be present in tenorite form and/or even in the glass (i.e., not as a crystalline phase).

In some embodiments, the total amount of Cu by wt % in the glasses may be in the range from about 10 to about 30, from about 15 to about 25, from about 11 to about 30, from about 12 to about 30, from about 13 to about 30, from about 14 to about 30, from about 15 to about 30, from about 16 to about 30, from about 17 to about 30, from about 18 to about 30, from about 19 to about 30, from about 20 to about 30, from about 10 to about 29, from about 10 to about 28, from about 10 to about 27, from about 10 to about 26, from about 10 to about 25, from about 10 to about 24, from about 10 to about 23, from about 10 to about 22, from about 10 to about 21, from about 10 to about 20, from about 16 to about 24, from about 17 to about 23, from about 18 to about 22, from about 19 to about 21 and all ranges and sub-ranges therebetween. In one or more embodiments, the ratio of Cu¹⁺ ions to the total amount Cu in the glass is about 0.5 or greater, 0.55 or greater, 0.6 or greater, 0.65 or greater, 0.7 or greater, 0.75 or greater, 0.8 or greater, 0.85 or greater, 0.9 or greater or even 1 or greater, and all ranges and sub-ranges therebetween. The amount of Cu and the ratio of Cu¹⁺ ions to total Cu may be determined by inductively coupled plasma (ICP) techniques known in the art.

In some embodiments, the glass may exhibit a greater amount of Cu¹⁺ and/or Cu⁰ than Cu′. For example, based on the total amount of Cu¹⁺, Cu¹⁺ and Cu⁰ in the glasses, the percentage of Cu¹⁺ and Cu⁰, combined, may be in the range from about 50% to about 99.9%, from about 50% to about 99%, from about 50% to about 95%, from about 50% to about 90%, from about 55% to about 99.9%, from about 60% to about 99.9%, from about 65% to about 99.9%, from about 70% to about 99.9%, from about 75% to about 99.9%, from about 80% to about 99.9%, from about 85% to about 99.9%, from about 90% to about 99.9%, from about 95% to about 99.9%, and all ranges and sub-ranges therebetween. The relative amounts of Cu¹⁺, Cu²⁺ and Cu⁰ may be determined using x-ray photoluminescence spectroscopy (XPS) techniques known in the art. The tables below report these amounts as measured by XPS. Specifically, the tables report the amount of Cu¹⁺ and the combination of Cu¹⁺ and Cu⁰. Without being bound by theory, it is believed that most of the embodiments shown in Table 1 show copper as being present in the form of Cu′+, under the conditions the XPS was performed.

The antimicrobial glass comprises at least a first phase and second phase. In one or more embodiments, the antimicrobial glass may include two or more phases wherein the phases differ based on the ability of the atomic bonds in the given phase to withstand interaction with a leachate. Specifically, the glass of one or more embodiments may include a first phase that may be described as a degradable phase and a second phase that may be described as a durable phase. The phrases “first phase” and “degradable phase” may be used interchangeably. The phrases “second phase” and “durable phase” may be used interchangeably. As used herein, the term “durable” refers to the tendency of the atomic bonds of the durable phase to remain intact during and after interaction with a leachate. As used herein, the term “degradable” refers to the tendency of the atomic bonds of the degradable phase to break during and after interaction with one or more leachates. In one or more embodiments, the durable phase includes SiO₂ and the degradable phase includes at least one of B₂O₃, P₂O₅ and R₂O (where R can include any one or more of K, Na, Li, Rb, and Cs). Without being bound by theory, it is believed that the components of the degradable phase (i.e., B₂O₃, P₂O₅ and/or R₂O) more readily interact with a leachate and the bonds between these components to one another and to other components in the antimicrobial glass more readily break during and after the interaction with the leachate. Leachates may include water, acids or other similar materials. In one or more embodiments, the degradable phase withstands degradation for 1 week or longer, 1 month or longer, 3 months or longer, or even 6 months or longer. In some embodiments, longevity may be characterized as maintaining antimicrobial efficacy over a specific period of time.

In one or more embodiments, the durable phase is present in an amount by weight that is greater than the amount of the degradable phase. In some instances, the degradable phase forms islands and the durable phase forms the sea surrounding the islands (i.e., the durable phase). In one or more embodiments, either one or both of the durable phase and the degradable phase may include cuprite. The cuprite in such embodiments may be dispersed in the respective phase or in both phases.

In some embodiments, phase separation occurs without any additional heat treatment of the antimicrobial glass. In some embodiments, phase separation may occur during melting and may be present when the glass composition is melted at temperatures up to and including about 1600° C. or 1650° C. When the glass is cooled, the phase separation is maintained.

The antimicrobial glass may be provided as a sheet or may have another shape such as particulate, fibrous, and the like. In one or more embodiments, as shown in FIGS. 1 and 2, the antimicrobial glass 100 includes a surface 101 and a surface portion 120 extending from the surface 101 into the antimicrobial glass at a depth of about 5 nanometers (nm) or less. The surface portion may include a plurality of copper ions wherein at least 75% of the plurality of copper ions includes Cu¹⁺ ions. For example, in some instances, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 98%, at least about 99% or at least about 99.9% of the plurality of copper ions in the surface portion includes Cu¹⁺ ions. In some embodiments, 25% or less (e.g., 20% or less, 15% or less, 12% or less, 10% or less or 8% or less) of the plurality of copper ions in the surface portion include Cu¹⁺ ions. For example, in some instances, 20% or less, 15% or less, 10% or less, 5% or less, 2% or less, 1% or less, 0.5% or less or 0.01% or less of the plurality of copper ions in the surface portion include Cu²⁺ ions. In some embodiments, the surface concentration of Cu¹⁺ ions in the antimicrobial glass is controlled. In some instances, a Cu¹⁺ ion concentration of about 4 ppm or greater can be provided on the surface of the antimicrobial glass.

The antimicrobial glass of one or more embodiments may a 2 log reduction or greater (e.g., 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5 and all ranges and sub-ranges therebetween) in a concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa, Methicillin Resistant Staphylococcus aureus, and E. coli, under the EPA Test. In some instances, the antimicrobial glass exhibits at least a 4 log reduction, a 5 log reduction or even a 6 log reduction in the concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa bacteria, Methicillin Resistant Staphylococcus aureus, and E. coli under the EPA Test.

The glasses described herein according to one or more embodiments may exhibit a 4 log reduction or greater (e.g., 5 log reduction or greater) in a concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa bacteria, Methicillin Resistant Staphylococcus aureus, and E. coli, under JIS Z 2801 (2000) testing conditions. One or more embodiments of the glasses described herein also exhibit a 4 log reduction or greater (e.g., 5 log reduction or greater) in a concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa, Methicillin Resistant Staphylococcus aureus, and E. coli, under the Modified JIS Z 2801 Test for Bacterial. As used herein, Modified JIS Z 2801 Test for Bacteria includes evaluating the bacteria under the standard JIS Z 2801 (2000) test with modified conditions comprising heating the glass or article to a temperature of about 23 degrees Celsius to about 37 degrees Celsius at a humidity of about 38 percent to about 42 percent for about 6 hours.

In one or more embodiments described herein, the antimicrobial glasses exhibit a 2 log reduction or greater, a 3 log reduction or greater, a 4 log reduction or greater, or a 5 log reduction or greater in Murine Norovirus under a Modified JIS Z 2801 for Viruses test. The Modified JIS Z 2801 (2000) Test for Viruses includes the following procedure. For each material (e.g., the articles or glass of one or more embodiments, control materials, and any comparative glasses or articles) to be tested, three samples of the material (contained in individual sterile petri dishes) are each inoculated with a 20 μL aliquot of a test virus (where antimicrobial activity is measured) or a test medium including an organic soil load of 5% fetal bovine serum with or without the test virus (where cytotoxicity is measured). The inoculum is then covered with a film and the film is pressed down so the test virus and/or or test medium spreads over the film, but does not spread past the edge of the film. The exposure time begins when each sample was inoculated. The inoculated samples are transferred to a control chamber set to room temperature (about 20° C.) in a relative humidity of 42% for 2 hours. Exposure time with respect to control samples are discussed below. Following the 2-hour exposure time, the film is lifted off using sterile forceps and a 2.00 mL aliquot of the test virus and/or test medium is pipetted individually onto each sample of material and the underside of the film (or the side of the film exposed to the sample) used to cover each sample. The surface of each sample is individually scrapped with a sterile plastic cell scraper to collect the test virus or test medium. The test virus and/or test medium is collected (at 10⁻² dilution), mixed using a vortex type mixer and serial 10-fold dilutions are prepared. The dilutions are then assayed for antimicrobial activity and/or cytotoxicity.

To prepare a control sample for testing antimicrobial activity (which are also referred to as “zero-time virus controls”) for the Modified JIS Z 2801 Test for Viruses, three control samples (contained in individual sterile petri dishes) are each inoculated with a 20 μL aliquot of the test virus. Immediately following inoculation, a 2.00 mL aliquot of test virus is pipetted onto each control sample. The surface of each sample was individually scrapped with a sterile plastic cell scraper to collect test virus. The test virus is collected (at 10⁻² dilution), mixed using a vortex type mixer, and serial 10-fold dilutions were prepared. The dilutions are assayed for antimicrobial activity.

To prepare controls samples for cytotoxicity (which are also referred to as “2 hour control virus”) for the Modified JIS Z 2801 Test for Viruses, one control sample (contained in an individual sterile petri dish) is inoculated with a 20 μL aliquot of a test medium containing an organic soil load (5% fetal bovine serum), without the test virus. The inoculum is covered with a film and the film is pressed so the test medium spreads over the film but does not spread past the edge of the film. The exposure time begins when each control sample is inoculated. The control sample is transferred to a controlled chamber set to room temperature (20° C.) in a relative humidity of 42% for a duration of 2 hours exposure time. Following this exposure time, the film is lifted off using sterile forceps and a 2.00 mL aliquot of the test medium is pipetted individually onto each control sample and the underside of the film (the side exposed to the sample). The surface of each sample is individually scrapped with a sterile plastic cell scraper to collect the test medium. The test medium is collected (at 10⁻² dilution), mixed using a vortex type mixer, and serial 10-fold dilutions were prepared. The dilutions were assayed for cytotoxicity.

The antimicrobial glass of one or more embodiments may exhibit the log reduction described herein for long periods of time. In other words, the antimicrobial glass may exhibit extended or prolonged antimicrobial efficacy. For example, in some embodiments, the antimicrobial glass may exhibit the log reductions described herein under the EPA Test, the JIS Z 2801 (2000) testing conditions, the Modified JIS Z 2801 Test for Bacteria and/or the Modified JIS Z 2801 Test for Viruses for up to 1 month, up to 3 months, up to 6 months or up to 12 months after the antimicrobial glass is formed or after the antimicrobial glass is combined with a carrier (e.g., polymers, monomers, binders, solvents and the like). These time periods may start at or after the antimicrobial glass is formed or combined with a carrier.

One or more embodiments, the antimicrobial glass may exhibit a preservative function, when combined with carriers described herein. In such embodiments, the antimicrobial glass may kill or eliminate, or reduce the growth of various foulants in the carrier. Foulants include fungi, bacteria, viruses and combinations thereof.

In one or more embodiments, the glasses and/or articles described herein leach the copper ions when exposed or in contact with a leachate. In one or more embodiments, the glass leaches only copper ions when exposed to leachates including water.

In one or more embodiments, the antimicrobial glass and/or articles described herein may have a tunable antimicrobial activity release. The antimicrobial activity of the glass and/or articles may be caused by contact between the antimicrobial glass and a leachate, such as water, where the leachate causes Cu¹⁺ ions to be released from the antimicrobial glass. This action may be described as water solubility and the water solubility can be tuned to control the release of the Cu⁺¹ ions.

In some embodiments, where the Cu¹⁺ ions are disposed in the glass network and/or form atomic bonds with the atoms in the glass network, water or humidity breaks those bonds and the Cu¹⁺ ions available for release and may be exposed on the glass or glass ceramic surface.

In one or more embodiments, the antimicrobial glass may be formed using formed in low cost melting tanks that are typically used for melting glass compositions such as soda lime silicate. The antimicrobial glass may be formed into a sheet using forming processes known in the art. For instance, example forming methods include float glass processes and down-draw processes such as fusion draw and slot draw.

The antimicrobial glass may be incorporated into a variety of articles, either alone or in combination with other materials, such as electronic devices (e.g., mobile phones, smart phones, tablets, video players, information terminal devices, laptop computer, etc.), architectural structures (e.g., countertops or walls), appliances (e.g., cooktops, refrigerator and dishwasher doors, etc.), information displays (e.g., whiteboards), and automotive components (e.g., dashboard panels, windshields, window components, etc.). When used in such articles, the antimicrobial glass can form at least part of the housing and/or display.

After formation, the antimicrobial glass may be formed into sheets and may be shaped, polished or otherwise processed for a desired end use. In some instances, the antimicrobial glass may be ground to a powder or particulate form. In other embodiments, the particulate antimicrobial glass may be combined with other materials or carriers into articles for various end uses. The combination of the antimicrobial glass and such other materials or carriers may be suitable for injection molding, extrusion or coatings or may be drawn into fibers. Such other materials or carriers may include polymers, monomers, binders, solvents, or a combination thereof as described herein. The polymer used in the embodiments described herein can include a thermoplastic polymer, a polyolefin, a cured polymer, an ultraviolet- or UV-cured polymer, a polymer emulsion, a solvent-based polymer, and combinations thereof. Examples of suitable polymers include, without limitation: thermoplastics including polystyrene (PS), high impact PS, polycarbonate (PC), nylon (sometimes referred to as polyamide (PA)), poly(acrylonitrile-butadiene-styrene) (ABS), PC-ABS blends, polybutyleneterephthlate (PBT) and PBT co-polymers, polyethyleneterephthalate (PET) and PET co-polymers, polyolefins (PO) including polyethylenes (PE), polypropylenes (PP), cyclicpolyolefins (cyclic-PO), modified polyphenylene oxide (mPPO), polyvinylchloride (PVC), acrylic polymers including polymethyl methacrylate (PMMA), thermoplastic elastomers (TPE), thermoplastic urethanes (TPU), polyetherimide (PEI) and blends of these polymers with each other. Suitable injection moldable thermosetting polymers include epoxy, acrylic, styrenic, phenolic, melamine, urethanes, polyesters and silicone resins. In other embodiments, the polymers may be dissolved in a solvent or dispersed as a separate phase in a solvent and form a polymer emulsion, such as a latex (which is a water emulsion of a synthetic or natural rubber), or plastic obtained by polymerization and used especially in coatings (as paint) and adhesives. Polymers may include fluorinated silanes or other low friction or anti-frictive materials. The polymers can contain impact modifiers, flame retardants, UV inhibitors, antistatic agents, mold release agents, fillers including glass, metal or carbon fibers or particles (including spheres), talc, clay or mica and colorants. Specific examples of monomers include catalyst curable monomers, thermally-curable monomers, radiation-curable monomers and combinations thereof.

In one example, acrylic latex paint may be combined with 20 wt % antimicrobial glass in particulate form and having a diameter of about 5 micrometers (μm). In some embodiments, the resulting combination of paint and antimicrobial glass included about 4 wt % CuO. In one or more embodiments, when combined with a carrier such as a polymer, monomer, binder or solvent, the amount of antimicrobial glass may be in the range from about 50 wt % to about 85 wt %. In some embodiments, the antimicrobial glass may be present in an amount in the range from about 55 wt % to about 85 wt %, from about 60 wt % to about 85 wt %, from about 65 wt % to about 85 wt %, from about 50 wt % to about 80 wt %, from about 50 wt % to about 75 wt %, from about 50 wt % to about 70 wt % and all ranges and sub-ranges therebetween, based on the total weight of the antimicrobial glass and carrier. In such embodiments, the total amount of CuO present in the may be about 20 wt %. In other embodiments, the amount of Cu₂O present in the antimicrobial glass and carrier combination may be in the range from about 10 wt % to about 20 wt % or more specifically, about 15%. The ratio of antimicrobial glass to carrier, by vol %, may be in the range from about 90:10 to about 10:90, or more specifically about 50:50.

In one or more embodiments, the antimicrobial glass may be provided in particulate form and may have a diameter in the range from about 0.1 micrometers (μm) to about 10 micrometers (μm), from about 0.1 micrometers (μm) to about 9 micrometers (μm), from about 0.1 micrometers (μm) to about 8 micrometers (μm), from about 0.1 micrometers (μm) to about 7 micrometers (μm), from about 0.1 micrometers (μm) to about 6 micrometers (μm), from about 0.5 micrometers (μm) to about 10 micrometers (μm), from about 0.75 micrometers (μm) to about 10 micrometers (μm), from about 1 micrometers (μm) to about 10 micrometers (μm), from about 2 micrometers (μm) to about 10 micrometers (μm), from about 3 micrometers (μm) to about 10 micrometers (μm) from about 3 micrometers (μm) to about 6 micrometers (μm), from about 3.5 micrometers (μm) to about 5.5 micrometers (μm), from about 4 micrometers (μm), to about 5 micrometers (μm), and all ranges and sub-ranges therebetween. The particulate antimicrobial glass may be substantially spherical or may have an irregular shape. The particles may be provided in a solvent and thereafter dispersed in a carrier as otherwise described herein.

Without being bound by theory it is believed that the combination of the antimicrobial glass described herein and a carrier, such as latex paint, provides substantially greater antimicrobial efficacy as compared to the same latex paint that includes only Cu₂O (cuprite), even when the same amount of copper is utilized. The presence of Cu¹⁺ crystals in the antimicrobial glasses described herein, even when present as cuprite, tends to remain in the Cu¹⁺ state. Without being bound by theory, it is believed that when Cu₂O is provided alone, separate from the glasses described herein, the Cu ions are less stable and may change to Cu²⁺ from Cu¹⁺.

The antimicrobial performance of the articles described herein may be impacted by the presence of a thin layer of polymer on the surface of the article. This thin layer may exhibit hydrophobic properties and may block the active copper species (Cu¹⁺) from exposure to air or from leaching to the surface. In one or more embodiments, the articles may use polymers that have balanced hydrophobic-hydrophilic properties that facilitate leaching of the active copper species. Examples of such polymers include hygroscopic/water soluble polymers and surfactants, amphiphilic polymers and/or a combination of amphiphilic polymers and hygroscopic materials. In one or more embodiments, the exposure to air and/or leaching of the active copper species to the surface may be facilitated by providing articles with an exposed treated surface. In one or more embodiments, the exposed treated surface is a surface that has been mechanically or chemically treated to expose at least some of the glass contained in the article to the air or to provide some of the glass at the surface of the article. Specific methods for providing an exposed treated surface include sanding, polishing, plasma treating (e.g., air, N₂, O₂, H₂, N₂ and/or Argon based plasma) and other methods that will remove a thin layer of the polymer material. In one or more alternative embodiments, the exposed treated surface includes functional groups, particularly hydroxyl and carbonyl groups, which are introduced into or to the exposed treated surface, to make such surface more hydrophilic. By providing an exposed treated surface, the active copper species is exposed to air or more readily leaches the surface of the article.

To improve processability, mechanical properties and interactions between the polymer and the glass described herein (including any fillers and/or additives that may be used), processing agents/aids may be included in the articles described herein. Exemplary processing agents/aids can include solid or liquid materials. The processing agents/aids may provide various extrusion benefits, and may include silicone based oil, wax and free flowing fluoropolymer. In other embodiments, the processing agents/aids may include compatibilizers/coupling agents, e.g., organosilicon compounds such as organo-silanes/siloxanes that are typically used in processing of polymer composites for improving mechanical and thermal properties. Such compatibilizers/coupling agents can be used to surface modify the glass and can include (3-acryloxy-propyl)trimethoxysilane; N-(2-aminoethyl)-3-aminopropyltrimethoxysilane; 3-aminopropyltri-ethoxysilane; 3-aminopropyltrimethoxysilane; (3-glycidoxypropyl)trimethoxysilane; 3-mercapto-propyltrimethoxysilane; 3-methacryloxypropyltrimethoxysilane; and vinyltrimethoxysilane.

In some embodiments, the articles described herein may include fillers including pigments, that are typically metal based inorganics can also be added for color and other purposes, e.g., aluminum pigments, copper pigments, cobalt pigments, manganese pigments, iron pigments, titanium pigments, tin pigments, clay earth pigments (naturally formed iron oxides), carbon pigments, antimony pigments, barium pigments, and zinc pigments.

After combining the antimicrobial glass described herein with a carrier, as described herein, the combination may be formed into a desired article. Examples of such articles include housings for electronic devices (e.g., mobile phones, smart phones, tablets, video players, information terminal devices, laptop computer, etc.), architectural structures (e.g., countertops or walls), appliances (e.g., cooktops, refrigerator and dishwasher doors, etc.), information displays (e.g., whiteboards), and automotive components (e.g., dashboard panels, windshields, window components, etc.).

In one or more embodiments, the articles may exhibit desired porosity and may be made into different shapes, including complex shapes and in different forms including plastics, rubbers and fiber/fabrics, which can have the same or different applications. Porous articles can also be used as antimicrobial filters. For example, the articles may be extruded into a honeycomb structure, which not only includes channels but also porous channel walls.

In other embodiments, the articles may include a high glass loading. Such articles may be formed from a melting process or the wet process. In such embodiments, in addition to using the articles themselves as an antimicrobial material, the polymer can be burnt out or removed to provide a pure copper glass antimicrobial article that is porous, with a simple or complex shape.

Cu(I) is an excellent catalyst for organic reactions, particularly for mild organic reactions, such as polymerization of acrylic monomers and oleochemical applications (e.g., hydrogenolysis of fatty esters to fatty alcohols including both methyl ester and wax ester processes, alkylation of alcohols with amines and amination of fatty alcohols), just to name a few. The articles described herein may be used for such applications.

Examples of the various uses and application of the articles described herein are shown in FIG. 13.

The articles described herein, including the antimicrobial glass and a polymer, may exhibit a 2 log reduction or greater in a concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa bacteria, Methicillin Resistant Staphylococcus aureus, and E. coli, under the EPA Test. In some instances, the article exhibits at least a 4 log reduction, a 5 log reduction or even a 6 log reduction in the concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa bacteria, Methicillin Resistant Staphylococcus aureus, and E. coli under the EPA Test.

The articles described herein according to one or more embodiments may exhibit a 2 log reduction or greater (e.g., 3 log reduction or greater, 4 log reduction or greater, or 5 log reduction or greater) in a concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa bacteria, Methicillin Resistant Staphylococcus aureus, and E. coli, under the JIS Z 2801 (2000) testing conditions and/or the Modified JIS Z 2801 Test for Bacteria. One or more embodiments of the articles described herein also exhibit a 4 log reduction or greater (e.g., 5 log reduction or greater) in a concentration of Murine Norovirus (strain MNV-1), under the Modified JIS Z 2801 Test for Viruses.

The articles of one or more embodiments may exhibit the log reduction described herein for long periods of time. In other words, the article may exhibit extended or prolonged antimicrobial efficacy. For example, in some embodiments, the article may exhibit the log reductions in bacteria and/or viruses described herein for up to 1 month, up to 3 months, up to 6 months or up to 12 months after the antimicrobial glass is formed or after the antimicrobial glass is combined with a carrier. These time periods may start at or after the antimicrobial glass is formed or combined with a carrier.

In one or more embodiments, the article may include a coating that may be applied on a surface, forming a coated surface. The coated surface may exhibit a stable color that does not undergo substantial changes after exposure to specific environments. For example, the coated surface may exhibit a delta (Δ) E of less than about 2 or even less than about 1, as measured by ASTM D2247, after being exposed to a temperature of 38° C. at 100% relative humidity for 7 days. As used herein, the phrase “delta (Δ) E” refers to the total color distance as measured by the distance between two color coordinates, provided under the CIELAB color space (ΔE_(ab)*=√{square root over ((L₂*−L₁*)²⁺ (a₂*−a₁*)²⁺ (b₂*−b₁*)²)}).

The coated surface may also exhibit chemical resistance to various chemicals, as measured by ASTM D1308, after exposure to chemicals in the center of a test piece for 1 hour.

The articles described herein may include pigments to impart color. Accordingly, the coatings made from such articles may exhibit a wide variety of colors, depending on the carrier color, mixture of carriers and amount of particle loading. Moreover, the articles and/or coatings described herein showed no adverse effect to paint adhesion as measured by ASTM D4541. In some instances, the adhesion of the article or coating to an underlying substrate was greater than the cohesive strength of the substrate. In other words, in testing, the adhesion between the coating and the substrate was so strong that the underlying substrate failed before the coating was separated from the surface of the substrate. For example, where the substrate includes wood, the adhesion between the coating and the substrate may be about 300 psi or greater, 400 psi or greater, 500 psi or greater, 600 psi or greater and all ranges-subranges therebetween, as measured by ASTM D4541. In some instances, the article, when applied to a substrate as a coating, exhibits an anti-sag index value of about 3 or greater, about 5 or greater, 7 or greater, 8 or greater, 9 or greater, 10 or greater, 11 or greater, 12 or greater, 13 or greater, 14 or greater or even 15 or greater, as measured by ASTM D4400.

The article and/or coating may exhibit sufficient durability for use in household and commercial applications. Specifically, the article, when applied to a substrate as a coating, exhibits a scrub resistance as measured by ASTM D4213 of about 4 or greater, 5 or greater, 6 or greater, 7 or greater and all ranges and sub-ranges therebetween.

In one or more embodiments, the article and/or coating may be resistant to moisture. For example, after exposure of the article and/or coating to an environment of up to about 95% relative humidity for 24 hours, the article and/or coating exhibited no change in antimicrobial activity.

One or more embodiments of the article may include an antimicrobial glass and a carrier with a loading level of the antimicrobial glass such that the article exhibits resistance or preservation against the presence or growth of foulants. Foulants include fungi, bacteria, viruses and combinations thereof. In some instances, the presence or growth of foulants in articles, such as paints, varnishes and the like, can cause color changes to the article, can degrade the integrity of the article and negatively affect various properties of the article. By including a minimum loading of antimicrobial glass, (e.g., about 5 wt % or less, about 4 wt % or less, about 3 wt % or less, about 2 wt % or less, or about 1 wt % or less) to the carrier, the foulants can be eliminated or reduced. In some instances, the carrier formulation need not include certain components, when fouling is eliminated or reduced. Thus, the carrier formulations used in one or more embodiments of the articles described herein may have more flexibility and variations than previously possible, when in known articles that do not include the antimicrobial glass.

Another aspect of this disclosure pertains to a method of making an antimicrobial article. In one or more embodiments, the method includes melting a glass composition (such as the compositions disclosed herein) to form a glass, forming the glass into particles, fibers or a combination thereof, dispersing the particles and/or fibers into a carrier (e.g., polymer) to provide a filled polymer and forming the filled polymer into an antimicrobial article.

In one or more embodiments, method includes loading a selected amount of glass into the polymer, depending on the application of the article. Various methods and processes can be used to such as, for example, an in situ process through mixing monomers with the glass (which may be ground into particles or other form) and then polymerized (into a thermosetting or a thermoplastic polymer matrix) or by mixing polymer with the glass through a process of solution or melt compounding (e.g. using a Brabender compounder or an extruder, single screw or twin screw, reactive or non-reactive), etc.

In one or more embodiments, forming the filled polymer into the antimicrobial article may include extruding or molding the filled polymer. In one or more embodiments, the antimicrobial article may be further processed to expose at least a portion of the glass to an exterior surface. The exterior surface may be a surface with which the user of the antimicrobial article interacts (e.g., the exterior surface of a mobile phone, the display of the mobile phone etc.). In one or more embodiments, the method may include removing a surface portion of the antimicrobial article to expose the glass dispersed in the filled polymer. Exemplary methods of removing a surface portion of the antimicrobial article may include etching (by plasma, acid or mechanical means such as sanding or polishing).

EXAMPLES

Various embodiments will be further clarified by the following examples.

Examples 1-62

Non-limiting examples of compositions described herein are listed in Table 1. The compositions in Table 1 were batched, melted and formed into glasses. Table 2 lists selected properties of the compositions of Table 1 and/or glasses formed therefrom, including the conditions for melting, annealing, appearance of the melt, density, anneal point (as measured by Beam Bending Viscometer (BBV)), strain point (as measured by BBV), softening point (as measured by parallel plate viscometer (PPV)), Vickers hardness, Vickers crack initiation, fracture toughness by chevron notch, coefficient of thermal expansion and the and other properties. Table 2 also includes the weight percent of Cu oxides, as determined by ICP techniques, and the ratio of Cu¹⁺:Cu¹⁺ for selected glasses.

Table 3 includes information related to the crystalline phases of crystal phase assemblages and/or crystal sizes of selected glasses as determined using X-ray diffraction (XRD) techniques known to those in the art, using such commercially available equipment as the model as a PW1830 (Cu Kα radiation) diffractometer manufactured by Philips, Netherlands. Spectra were typically acquired for 2θ from 5 to 80 degrees. Table 3 also includes elemental profile information of selected glasses determined XPS techniques.

The glasses where then tested under the EPA test using Staphylococcus aureus under two conditions, as shown in Table 4. Table 4 also includes the total amount of Cu and Cu¹⁺ found in selected examples, as determined by ICP techniques.

TABLE 1 Example Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Batched Composition (mol %) SiO₂ 65 65 60 60 60 Al₂O₃ 17.5 17.5 20 15 15 CuO 17.5 17.5 20 20 20 Na₂O 5 K₂O 5 B₂O₃ P₂O₅ ZnO Batched Composition (wt %) SiO₂ 55.2 55.2 49.8 51.2 50.1 Al₂O₃ 25.2 25.2 28.2 21.7 21.3 CuO 19.7 19.7 22.0 22.6 22.1 Na₂O 4.4 K₂O 6.5 B₂O₃ P₂O₅ ZnO Example Ex. 6 Ex. 7 Ex. 8 Ex. 9 Ex. 10 Batched Composition (mol %) SiO₂ 60 60 60 60 60 Al₂O₃ 10 10 5 5 CuO 20 20 20 20 20 Na₂O 10 10 5 K₂O 10 5 10 10 B₂O3 10 P₂O5 ZnO Batched Composition (wt %) SiO₂ 52.7 50.4 53.0 51.8 52.8 Al₂O₃ 14.9 14.2 7.5 7.3 0.0 CuO 23.3 22.2 23.4 22.9 23.3 Na₂O 9.1 9.1 4.5 K₂O 13.2 6.9 13.5 13.8 B₂O₃ 10.2 P₂O₅ ZnO Example Ex. 11 Ex. 12 Ex. 13 Ex. 14 Ex. 15 Batched Composition (mol %) SiO₂ 60 60 60 50 50 Al₂O₃ 5 CuO 20 20 20 20 20 Na₂O K₂O 10 10 10 10 10 B₂O₃ 5 10 P₂O₅ 10 5 5 10 20 ZnO Batched Composition (wt %) SiO₂ 47.7 49.0 50.1 39.3 35.9 Al₂O₃ 6.9 CuO 21.0 21.6 22.1 20.8 19.0 Na₂O K₂O 12.5 12.8 13.1 12.3 11.2 B₂O₃ 4.8 9.1 P₂O₅ 18.8 9.6 9.9 18.5 33.9 ZnO 0.05 MgO 0.05 Fe₂O₃ 0.11 CaO 0.01 Example Ex. 16 Ex. 17 Ex. 18 Ex. 19 Ex. 20 Batched Composition (mol %) SiO₂ 50 50 50 50 50 Al₂O₃ 25 20 25 25 20 CuO 25 30 25 25 20 Na₂O 5 10 K₂O 5 B₂O₃ P₂O₅ ZnO Batched Composition (wt %) SiO₂ 39.8 40.4 38.3 37.5 41.4 Al₂O₃ 33.8 27.4 32.5 31.8 28.1 CuO 26.4 32.1 25.3 24.8 21.9 Na₂O 3.9 8.5 K₂O 5.9 B₂O₃ P₂O₅ ZnO Example Ex. 21 Ex. 22 Ex. 23 Ex. 24 Ex. 25 Batched Composition (mol %) SiO₂ 50 60 60 50 60 Al₂O₃ 20 5 5 CuO 20 20 20 20 20 Na₂O 10 K₂O 10 10 10 10 B₂O3 5 10 P₂O5 5 5 10 5 ZnO Batched Composition (wt %) SiO₂ 39.7 49.0 50.1 39.3 51.2 Al₂O₃ 26.9 6.9 7.2 CuO 21.0 21.6 22.1 20.8 22.6 Na₂O 8.8 K₂O 12.4 12.8 13.1 12.3 B₂O₃ 4.8 9.1 P₂O₅ 9.6 9.9 18.5 10.1 ZnO Example Ex. 26 Ex. 27 Ex. 28 Ex. 29 Ex. 30 Batched Composition (mol %) SiO₂ 60 50 50 50 55 Al₂O₃ 5 5 CuO 20 20 20 20 20 Na₂O 10 10 10 K₂O 10 10 B₂O3 5 10 10 10 10 P₂O5 5 10 5 5 5 ZnO Batched Composition (wt %) SiO₂ 52.5 41.0 42.1 40.3 45.6 Al₂O₃ 7.1 6.8 CuO 23.1 21.7 22.3 21.3 22.0 Na₂O 9.0 8.5 8.7 K₂O 12.6 13.0 B₂O₃ 5.1 9.5 9.8 9.3 9.6 P₂O₅ 10.3 19.4 10.0 9.5 9.8 ZnO Example Ex. 31 Ex. 32 Ex. 33 Ex. 34 Ex. 35 Batched Composition (mol %) SiO₂ 55 60 55 60 55 Al₂O₃ 5 5 CuO 20 20 20 20 20 Na₂O 10 15 15 K₂O 10 10 B₂O₃ 10 10 P₂O₅ 5 5 5 5 5 ZnO Batched Composition (wt %) SiO₂ 47.7 52.7 46.9 49.0 45.6 Al₂O₃ 7.2 6.9 CuO 23.0 23.3 22.6 21.6 22.0 Na₂O 9.0 13.6 13.2 K₂O 12.8 13.0 B₂O₃ 10.1 9.6 P₂O₅ 10.3 10.4 10.1 9.6 9.8 ZnO Example Ex. 36 Ex. 37 Ex. 38 Ex. 39 Ex. 40 Batched Composition (mol %) SiO₂ 50 45 40 55 55 Al₂O₃ CuO 20 20 20 20 20 Na₂O K₂O 10 10 12.5 10 10 B₂O₃ 10 10 10 10 10 P₂O₅ 5 5 5 5 5 ZnO 5 10 12.5 Batched Composition (wt %) SiO₂ 40.9 36.3 31.6 45.6 45.6 Al₂O₃ CuO 21.6 21.3 20.9 22.0 22.0 Na₂O K₂O 12.8 12.6 15.5 13.0 13.0 B₂O₃ 9.5 9.3 9.2 9.6 9.6 P₂O₅ 9.7 9.5 9.3 9.8 9.8 ZnO 5.5 10.9 13.4 Example Ex. 41 Ex. 42 Ex. 43 Ex. 44 Ex. 45 Batched Composition (mol %) SiO₂ 51.5 51.5 48 48 55 Al₂O₃ 0 0 0 0 CuO 25 25 30 30 20 Na₂O 0 0 0 0 K₂O 9.4 9.4 8.8 8.8 10 B₂O₃ 9.4 9.4 8.8 8.8 10 P₂O₅ 4.7 4.7 4.4 4.4 5 ZnO 0 0 0 0 55 Batched Composition (wt %) SiO₂ 42.4 42.4 39.3 39.3 Al₂O₃ 0.0 0.0 0.0 0.0 CuO 27.3 27.3 32.5 32.5 Na₂O 0.0 0.0 0.0 0.0 K₂O 12.1 12.1 11.3 11.3 B₂O₃ 9.0 9.0 8.4 8.4 P₂O₅ 9.2 9.2 8.5 8.5 ZnO 0.0 0.0 0.0 0.0 Example Ex. 46 Ex. 47 Ex. 48 Ex. 49 Ex. 50 Batched Composition (mol %) SiO₂ 50 50 50 50 55 Al₂O₃ 0 0 0 0 0 CuO 20 20 20 20 20 Na₂O 0 0 0 0 0 K₂O 10 10 10 10 10 B₂O₃ 10 10 10 10 10 P₂O₅ 5 5 5 5 5 ZnO 0 0 0 0 0 TiO₂ 5 0 0 0 0 Fe₂O₃ 0 5 0 0 0 Cr₂O₃ 0 0 5 0 0 Co₃O₄ 0 0 0 5 0 NiO 0 0 0 0 0 Example Ex. 51 Ex. 52 Ex. 53 Ex. 54 Ex. 55 Ex. 56 Batched Composition (mol %) SiO₂ 40 45 50 55 50 45 Al₂O₃ 15 15 15 15 15 CuO 20 20 20 20 20 35 Na₂O K₂O 10 10 10 5 5 7.5 B₂O₃ 10 5 0 0 5 7.5 P₂O₅ 5 5 5 5 5 5 ZnO 0 0 0 0 0 TiO₂ 0 0 0 0 0 Fe₂O₃ 0 0 0 0 0 Cr₂O₃ 0 0 0 0 0 Co₃O₄ 0 0 0 0 0 NiO 0 0 0 0 0 Example Ex. 57 Ex. 58 Ex. 59 Ex. 60 Ex. 61 Ex. 62 Batched Composition (mol %) SiO₂ 55 50 45 45 45 45 Al₂O₃ 0 0 CuO 30 35 40 25 25 30 Na₂O 0 0 K₂O 10 10 10 10 10 10 B₂O₃ 0 0 P₂O₅ 5 5 5 5 5 5 ZnO 0 0 TiO₂ 0 10 Fe₂O₃ 0 0 Cr₂O₃ 0 0 Co₃O₄ 15 0 0 NiO 15 0

TABLE 2 Example Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Melt Temp (° C.) 1500 1650 1650 1650 1650 Melt Time (hrs) 6 overnight overnight overnight overnight Crucible Type Alumina Quartz Quartz Quartz Quartz Anneal Temp (° C.) 700 700 700 700 700 Melt Appearance Very High High Grey Grey Poor, Quality, Quality, Surface, Surface, full of Surface Surface black black large Oxidation, Oxidation, interior interior bubbles Gray Gray surface, surface, black black interior interior Density by buoyancy (g/cm³) 2.705 2.781 2.758 2.741 Effective molecular wt (g/mol) 70.821 70.821 72.354 Molar Volume (cm³/mol) 26.2 26.0 Anneal Point by BBV (° C.) 694.1 684.9 598.6 Strain Point by BBV (° C.) 652.5 642.3 558.9 Softening Point by PPV (° C.) xstallized xstallized Vickers Hardness (kgf/mm²) 595 586 Vickers Crack Initiation (kgf) 1-2 1-2 Fracture Toughness by 0.875 0.887 Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) 1.06 1.15 ICP wt % oxides (Cu) 19.6 19 21.6 ratio Cu⁺¹/Cu²⁺ Example Ex. 6 Ex. 7 Ex. 8 Ex. 9 Ex. 10 Melt Temp (° C.) 1650 1650 1650 1650 1650 Melt Time (hrs) overnight overnight overnight overnight overnight Crucible Type Quartz Quartz Quartz Quartz Quartz Anneal Temp (° C.) 700 700 700 700 600 Melt Appearance Black and Black and Black and Grey gray gray grey lustrous lustrous lustrous surface, surface, surface, surface, primarily dark brown brown black yellow and and interior interior yellow yellow with some interior interior green and brown streaks Density by buoyancy (g/cm³) 2.706 2.666 2.596 2.716 Effective molecular wt (g/mol) Molar Volume (cm³/mol) Anneal Point by BBV (° C.) 737.2 575.7 Strain Point by BBV (° C.) 684.4 535.2 Softening Point by PPV (° C.) Vickers Hardness (kgf/mm²) Vickers Crack Initiation (kgf) Fracture Toughness by Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) ICP wt % oxides (Cu) ratio Cu⁺¹/Cu²⁺ Example Ex. 11 Ex. 12 Ex. 13 Ex. 14 Ex. 15 Melt Temp (° C.) 1650 1650 1650 1650 1650 Melt Time (hrs) overnight overnight overnight overnight overnight Crucible Type Quartz Quartz Quartz Quartz Quartz Anneal Temp (° C.) 600 700 600 600 600 Melt Appearance Ceramic, Shiny Shiny Dark Ceramic, brittle, metallic metallic yellow grey gray, surface, surface, surface surface, brown, dark dark w/some light and yellow yellow ceramic, brown green interior interior dark interior yellow interior w/some ceramic Density by buoyancy (g/cm³) 2.669 2.673 2.608 Effective molecular wt (g/mol) Molar Volume (cm³/mol) Anneal Point by BBV (° C.) Strain Point by BBV (° C.) 701 569 572.5 Softening Point by PPV (° C.) 759.8 602.8 510.7 Vickers Hardness (kgf/mm²) Vickers Crack Initiation (kgf) Fracture Toughness by Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) ICP wt % oxides (Cu) ratio Cu⁺¹/Cu²⁺ Example Ex. 16 Ex. 17 Ex. 18 Ex. 19 Ex. 20 Melt Temp (° C.) 1650 1650 1650 1650 1650 Melt Time (hrs) overnight overnight overnight overnight overnight Crucible Type Quartz Quartz Quartz Quartz Quartz Anneal Temp (° C.) 700 700 700 700 700 Melt Appearance Grey Grey Grey Grey Grey Surface, Surface, Surface, Surface, Surface, black black black black black interior, interior interior interior interior copper precipitated Density by buoyancy (g/cm³) 2.91 2.901 2.887 2.876 2.797 Effective molecular wt (g/mol) Molar Volume (cm³/mol) Anneal Point by BBV (° C.) Strain Point by BBV (° C.) Softening Point by PPV (° C.) Vickers Hardness (kgf/mm²) Vickers Crack Initiation (kgf) Fracture Toughness by Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) ICP wt % oxides (Cu) ratio Cu⁺¹/Cu²⁺ Example Ex. 21 Ex. 22 Ex. 23 Ex. 24 Ex. 25 Melt Temp (° C.) 1650 1650 1650 1650 1650 Melt Time (hrs) Overnight overnight overnight Overnight overnight Crucible Type Quartz Quartz Quartz Quartz Quartz Anneal Temp (° C.) 700 650 650 650 650 Melt Appearance Grey Grey Grey Crystallized Grey Surface, Surface, Surface, Surface, yellow Yellow/ Yellow/ Yellow/ interior orange orange orange interior interior interior (looks more crystalline than Ex. 22) Density by buoyancy (g/cm³) 2.774 Effective molecular wt (g/mol) Molar Volume (cm³/mol) Anneal Point by BBV (° C.) Strain Point by BBV (° C.) Softening Point by PPV (° C.) Vickers Hardness (kgf/mm²) Vickers Crack Initiation (kgf) Fracture Toughness by Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) ICP wt % oxides (Cu) ratio Cu⁺¹/Cu²⁺ Example Ex. 26 Ex. 27 Ex. 28 Ex. 29 Ex. 30 Melt Temp (° C.) 1650 1650 1650 1650 1650 Melt Time (hrs) overnight overnight overnight overnight overnight Crucible Type Quartz Quartz Quartz Quartz Quartz Anneal Temp (° C.) 650 650 650 650 650 Melt Appearance Grey Surface, crystallized Shiny exterior, Shiny exterior, Shiny exterior, Yellow/orange yellow/orange yellow/orange yellow/orange interior (looks interior interior interior more crystalline than Ex. 23) Density by buoyancy (g/cm³) 2.626 Effective molecular wt (g/mol) Molar Volume (cm³/mol) Anneal Point by BBV (° C.) Strain Point by BBV (° C.) 602.4 Softening Point by PPV (° C.) 544.4 Vickers Hardness (kgf/mm²) Vickers Crack Initiation (kgf) Fracture Toughness by Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) ICP wt % oxides (Cu) ratio Cu⁺¹/Cu²⁺ Example Ex. 31 Ex. 32 Ex. 33 Ex. 34 Ex. 35 Melt Temp (° C.) 1650 1650 1650 1650 1650 Melt Time (hrs) overnight overnight overnight overnight overnight Crucible Type Quartz Quartz Quartz Quartz Quartz Anneal Temp (° C.) 650 650 650 650 650 Melt Appearance Shiny Lighter Lighter Orange Orange exterior, yellow, yellow, Interior, Interior, yellow/orange more crystallized shiny shiny interior crystalline metallic metallic surface surface Density by buoyancy (g/cm³) Effective molecular wt (g/mol) Molar Volume (cm³/mol) Anneal Point by BBV (° C.) Strain Point by BBV (° C.) Softening Point by PPV (° C.) Vickers Hardness (kgf/mm²) Vickers Crack Initiation (kgf) Fracture Toughness by Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) ICP wt % oxides (Cu) ratio Cu⁺¹/Cu²⁺ Example Ex. 36 Ex. 37 Ex. 38 Ex. 39 Ex. 40 Melt Temp (° C.) 1650 1650 1650 1650 1650 Melt Time (hrs) overnight overnight overnight overnight overnight Crucible Type Quartz Quartz Quartz Quartz Quartz Anneal Temp (° C.) 650 650 650 none 650 Melt Appearance Orange Orange Orange Yellow, Orange Interior, Interior, Interior, Orange Interior, shiny shiny shiny shiny metallic metallic metallic metallic surface surface surface surface Density by buoyancy (g/cm³) Effective molecular wt (g/mol) Molar Volume (cm³/mol) Anneal Point by BBV (° C.) Strain Point by BBV (° C.) Softening Point by PPV (° C.) Vickers Hardness (kgf/mm²) Vickers Crack Initiation (kgf) Fracture Toughness by Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) ICP wt % oxides (Cu) ratio Cu⁺¹/Cu²⁺ Example Ex. 41 Ex. 42 Ex. 43 Ex. 44 Ex. 46 Melt Temp (° C.) 1650 1650 1650 1650 Melt Time (hrs) overnight overnight overnight overnight Crucible Type Quartz Quartz Quartz Quartz Anneal Temp (° C.) none 650 none 650 Melt Appearance Yellow, Orange Yellow, Orange reddish Orange Interior, shiny Orange Interior, shiny orange metallic metallic surface surface Density by buoyancy (g/cm³) 2.816 Effective molecular wt (g/mol) Molar Volume (cm³/mol) Anneal Point by BBV (° C.) Strain Point by BBV (° C.) Softening Point by PPV (° C.) Vickers Hardness (kgf/mm²) Vickers Crack Initiation (kgf) Fracture Toughness by Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) ICP wt % oxides (Cu) ratio Cu⁺¹/Cu²⁺ Example Ex. 47 Ex. 48 Ex. 49 Ex. 50 Ex. 51 Melt Temp (° C.) Melt Time (hrs) Crucible Type Anneal Temp (° C.) Melt Appearance orange greenish light green, Yellow crystallized greener and than Ex. 48 Black Density by buoyancy (g/cm³) Effective molecular wt (g/mol) Molar Volume (cm³/mol) Anneal Point by BBV (° C.) Strain Point by BBV (° C.) Softening Point by PPV (° C.) Vickers Hardness (kgf/mm²) Vickers Crack Initiation (kgf) Fracture Toughness by Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) ICP wt % oxides (Cu) ratio Cu⁺¹/Cu²⁺ Example Ex. 52 Ex. 53 Ex. 54 Ex. 55 Ex. 56 Melt Temp (° C.) Melt Time (hrs) Crucible Type Anneal Temp (° C.) Melt Appearance Yellow Yellow Black with Black with Pumpkin- and some orange some colored Brown on bottom orange on edges Density by buoyancy (g/cm³) Effective molecular wt (g/mol) Molar Volume (cm³/mol) Anneal Point by BBV (° C.) Strain Point by BBV (° C.) Softening Point by PPV (° C.) Vickers Hardness (kgf/mm²) Vickers Crack Initiation (kgf) Fracture Toughness by Chevron Notch (MPa m^(0.5)) CTE (ppm/° C.) ICP wt % oxides (Cu) ratio Cu⁺¹/Cu²⁺ *The term ″crystallized″ as used here refers to a non-glassy appearance.

TABLE 3 Example Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 XRD powder none Tenorite (CuO) Tenorite (CuO) XRD surface Tenorite (CuO) Tenorite (CuO) XPS vacuum fracture + 2 min air % Cul¹⁺ and Cu⁰ 85.2 % Cu²⁺ 14.8 StDev 1 XPS vacuum fracture % Cul¹⁺ and Cu⁰ % Cu²⁺ StDev Example Ex. 6 Ex. 7 Ex. 8 Ex. 9 Ex. 10 XRD powder Tenorite (CuO) Tenorite (CuO) Cuprite Cuprite (Cu₂O) and Cuprite and Cuprite (Cu₂O) (Cu₂O) (Cu₂O) XRD surface Tenorite (CuO) Tenorite (CuO) no Tenorite (CuO) and Cuprite and Cuprite peaks and Cuprite (Cu₂O) (Cu₂O) (Cu₂O) XPS vacuum fracture + 2 min air % Cul¹⁺ and Cu⁰ 84.2 74.6 % Cu²⁺ 15.8 25.4 StDev 0.1 1.5 XPS vacuum fracture % Cul¹⁺ and Cu⁰ % Cu²⁺ StDev Example Ex. 11 Ex. 12 Ex. 13 Ex. 14 Ex. 15 XRD powder Cuprite (Cu₂O), K1 − Cuprite Cuprite xAl¹⁺xSi1 − xO4, (Cu₂O) (Cu₂O) Al2O3 * 0.95P2O5, Cu1.82K0.2(Al3.9Si8.1O24), K2SiO3 XRD surface Tenorite (CuO), Cuprite (Cu₂O), Cuprite Cuprite K1 − xAl¹⁺xSi1 − xO4, (Cu₂O) (Cu₂O) Al2O3 * 0.95P2PO5 XPS vacuum fracture + 2 min air % Cul¹⁺ and Cu⁰ 92.4 80.3 91.3 % Cu²⁺ 7.6 19.7 8.7 StDev 1.2 2.5 0.4 XPS vacuum fracture % Cul¹⁺ and Cu⁰ 87.1 93.1 % Cu²⁺ 12.9 6.9 StDev 2.6 0.6 Example Ex. 16 Ex. 17 Ex. 18 Ex. 19 Ex. 20 XRD powder Tenorite Tenorite Tenorite none Tenorite (CuO) (CuO) (CuO) (CuO) XRD surface Tenorite Tenorite Tenorite Tenorite Tenorite (CuO) (CuO) (CuO) (CuO) (CuO) XPS vacuum fracture + 2 min air % Cul¹⁺ and Cu⁰ % Cu²⁺ StDev XPS vacuum fracture % Cul¹⁺ Cu0 % Cu²⁺ StDev Example Ex. 21 Ex. 22 Ex. 23 Ex. 24 Ex. 25 XRD powder Cuprite Cuprite, Cuprite Cristobalite, Cuprite, (Cu₂O) Tenorite, Copper Sodium Sodium Silicate Borate (Na₂Si₂O₅), (Na₂B₁₈O₈), Aluminum Potassium Phosphate Aluminum (AlPO₄) Silicate (KAlSiO₄) XRD surface Tenorite Cuprite, Cuprite, Cuprite Cuprite, (CuO) Tenorite, Tenorite, Tenorite, Sodium Sodium Sodium Borate Borate Silicate (Na₂Si₂O₅), Aluminum Phosphate (AlPO₄) XPS vacuum fracture + 2 min air % Cul¹⁺ and Cu⁰ 81.7 % Cu²⁺ 18.3 StDev 0.2 XPS vacuum fracture % Cul¹⁺ and Cu⁰ % Cu²⁺ StDev Example Ex. 26 Ex. 27 Ex. 28 Ex. 29 Ex. 30 XRD powder Cristobalite, Copper, Cuprite Cuprite Cuprite Cuprite, Cuprite, Copper Sodium Phosphate Copper (Cu₃(PO₄)₂ Phosphate (Na₆Cu₉(PO₄)₆) XRD surface Cristobalite, Copper, Cuprite, Cuprite Cuprite, Cuprite, Cuprite, Sodium Tenorite Tenorite, Tenorite, Borate Copper Sodium Hydrate Phosphate Copper Phosphate XPS vacuum fracture + 2 min air % Cul¹⁺ and Cu⁰ 87.1 75 % Cu²⁺ 12.9 25 StDev 1.2 0.2 XPS vacuum fracture % Cul¹⁺ and Cu⁰ % Cu²⁺ StDev Example Ex. 31 Ex. 32 Ex. 33 Ex. 34 Ex. 35 XRD powder Cuprite Cristobalite, Cuprite, Cuprite, Sodium Sodium Phosphate, Phosphate Na_(0.24)H_(4.9)((Al_(5.14)- (Na₃PO₄), Si_(48.86))O₁₀₆)(H₂O)_(26.5) Aluminum Phosphate Hydrate (AlPO₄ * xH₂O), Copper Phosphate (Cu₅P₂O₁₀) XRD surface Cuprite, Cristobalite, Tenorite, Tenorite, Tenorite, Sodium Tincalconite Sodium Phosphate, (Na₂B₄O₇ * 5H₂O), Phosphate Cuprite Copper (Na₃PO₄), Phosphate Aluminum Hydrate Phosphate Cu₃(PO₃)₆ * 14 Hydrate H₂O (AlPO₄ * xH₂O), Copper Phosphate (Cu₅P₂O₁₀) XPS vacuum fracture + 2 min air % Cul¹⁺ and Cu⁰ 68.7 % Cu²⁺ 31.3 StDev 0.6 XPS vacuum fracture % Cul¹⁺ and Cu⁰ % Cu²⁺ StDev Example Ex. 36 Ex. 37 Ex. 38 Ex. 39 Ex. 40 XRD powder Cuprite, Cuprite, Cuprite, Cuprite Cuprite Potassium Zinc Potassium Zinc Potassium Phosphate Phosphate, Zinc (KZnPO₄) Potassium Zinc Phosphate Silicate (KZnPO₄), (K_(1.10)Zn_(0.55)Si_(1.45)O₄), Potassium Potassium Zinc Silicate, Zinc Phosphate Potassium (K₆Zn(P₂O₇)₂ Zinc Phosphate XRD surface Cuprite, Tenorite, Tenorite, Potassium Zinc Copper Zinc Potassium Phosphate Phosphate Zinc (KZnPO₄), (CuZn(P₂O₇), Phosphate, Copper Silicon Potassium Potassium Phosphide Phosphate Zinc Silicate, (Cu_(0.56)Si_(1.44))P₂, (K₄(P₂O₈), Potassium Tenorite Aluminum Copper Oxide Phosphate (K₃CuO₄), (AlPO₄) Cuprite, Copper Oxide Phosphate (Cu₄O(PO₄)₂ XPS vacuum fracture + 2 min air % Cul¹⁺ and Cu⁰ % Cu²⁺ StDev XPS vacuum fracture % Cul¹⁺ and Cu⁰ % Cu²⁺ StDev Example Ex. 41 Ex. 42 Ex. 43 Ex. 44 Ex. 45 XRD powder Cuprite Cuprite Cuprite Cuprite XRD surface XPS vacuum fracture + 2 min air % Cul¹⁺ Cu0 % Cu²⁺ StDev XPS vacuum fracture % Cul¹⁺ Cu0 % Cu²⁺ StDev Example Ex. 46 Ex. 47 Ex. 48 Ex. 49 Ex. 50 XRD powder Cuprite, Cuprite Copper Titanium Oxide, Anatase XRD surface Cuprite, Copper Titanium Oxide, Anatase XPS vacuum fracture + 2 min air % Cul¹⁺ Cu0 % Cu²⁺ StDev XPS vacuum fracture % Cul¹⁺ Cu0 % Cu²⁺ StDev Example Ex. 51 Ex. 52 Ex. 53 Ex. 54 Ex. 55 XRD powder Cuprite Tenorite and cuprite tenorite and tenorite and cuprite cuprite cuprite XRD surface Tenorite and Tenorite and Tenorite and tenorite tenorite cuprite cuprite cuprite XPS vacuum fracture + 2 min air % Cul¹⁺ Cu0 % Cu²⁺ StDev XPS vacuum fracture % Cul¹⁺ Cu0 % Cu²⁺ StDev Example Ex. 56 XRD powder Cuprite and copper potassium oxide XRD surface cuprite and tenorite and potassium borate XPS vacuum fracture + 2 min air % Cul¹⁺ Cu0 % Cu²⁺ StDev XPS vacuum fracture % Cul¹⁺ Cu0 % Cu²⁺ StDev

TABLE 4 Example Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Coupon Testing As-Received <log 1 <log 1 <log 1 <log 1 EPA Test (S. Aureus) Coupon Testing As-Received <log 1 EPA Re-Test Coupon Testing 1 Day 85° C./85% RH EPA Test ICP Total Cu in wt % 21.6 21.7 ICP Cu⁺¹/total Cu 0.86 0.87 0.88 Example Ex. 6 Ex. 7 Ex. 8 Ex. 9 Ex. 10 Coupon Testing As-Received >log 3 log 2.84 <log 1 <log 1 EPA Test (S. Aureus) Coupon Testing As-Received >log 1 <log 1 <log 1 EPA Re-Test Coupon Testing 1 Day 85° C./85% RH EPA Test ICP Total Cu in wt % 19.6 15.8 22 ICP Cu⁺¹/total Cu 0.88 0.86 0.78 0.8 Example Ex. 11 Ex. 12 Ex. 13 Ex. 14 Ex. 15 Coupon Testing As-Received >log 4 >log 3 >log 6 EPA Test (S. Aureus) Coupon Testing As-Received >log 3 >log 4 EPA Re-Test Coupon Testing 1 Day 85° C./85% RH EPA Test ICP Total Cu in wt % 20.8 20.8 20.5 ICP Cu⁺¹/total Cu 0.85 0.77 0.85 Example Ex. 21 Ex. 22 Ex. 23 Ex. 24 Ex. 25 Coupon Testing As-Received <log 1 <log 1 >log 4 EPA Test (S. Aureus) Coupon Testing As-Received EPA Re-Test Coupon Testing 1 Day <log 1 <log 1 <log 1 85° C./85% RH EPA Test ICP Total Cu in wt % 18.1 21.5 21.9 21.5 ICP Cu⁺¹/total Cu 0.92 0.8 0.8 0.85 Example Ex. 26 Ex. 27 Ex. 28 Ex. 29 Ex. 30 Coupon Testing As-Received >log 3 >log 3 >log 4 EPA Test (S. Aureus) Coupon Testing As-Received EPA Re-Test Coupon Testing 1 Day 85° C./85% RH EPA Test >log 2 >log 2 >log 4 ICP Total Cu in wt % 21.3 21.4 22.2 21.6 ICP Cu⁺¹/total Cu 0.75 0.82 0.89 0.86 Example Ex. 31 Ex. 32 Ex. 33 Ex. 34 Ex. 35 Coupon Testing As-Received >log 3 EPA Test (S. Aureus) Coupon Testing As-Received EPA Re-Test Coupon Testing 1 Day >log 2 85° C./85% RH EPA Test ICP Total Cu in wt % 22.4 19.8 19.1 ICP Cu⁺¹/total Cu 0.86 0.77 0.85 Example Ex. 41 Ex. 42 Ex. 43 Ex. 44 Ex. 46 Coupon Testing As-Received <log 6 log 5.93 0.53 EPA Test (S. Aureus) Coupon Testing As-Received EPA Re-Test Coupon Testing 1 Day 85° C./85% RH EPA Test ICP Total Cu in wt % ICP Cu⁺¹/total Cu 0.88 Example Ex. 49 Ex. 56 Ex. 58 Coupon Testing As-Received 1.42 6.151 6.151 EPA Test (S. Aureus) Coupon Testing As-Received EPA Re-Test Coupon Testing 1 Day 85° C./85% RH EPA Test ICP Total Cu in wt % ICP Cu⁺¹/total Cu

Regarding Example 13, SEM images indicate that phase separation occurred and included a glassy matrix phase and a dispersed glassy second phase. The dispersed phase is considered a degradable phase and included cuprite crystals. The degradation of the dispersed phase was evident when that phase partially dissolved when the formed glass was polished in water. EDS analysis showed a glassy phase enriched in silicon (i.e., a durable phase) relative to both the glassy second phase and crystalline phase. The crystalline phase was the most copper-rich. Without being bound by theory, it is believed that the glassy second phase is enriched in boron. The phase separation of the degradable phase (including the precipitation of cuprite crystals) occurred readily without additional heat treatment beyond simple post-melt annealing.

FIGS. 3-5 are TEM and SEM images of a glasses made from the composition of Example 30. FIG. 3 shows a TEM image in which the darkest areas indicate a silica-rich glassy phase and the lighter areas are phase-separated glassy regions enriched with phosphorus, boron and potassium. As discussed above, these phase-separated glassy regions are degradable regions, and the silica-rich glassy phase is a durable phase. Both the degradable phase and durable phase form the glass phase of the glass. The lightest areas shown in the TEM image of FIG. 3 indicate cuprite crystals. The areas that are appear darker than the lightest areas indicate phase-separated glassy regions enriched with phosphorus, boron and potassium (i.e., the degradable phase). The silica-rich glassy phase is indicated by the darkest regions in FIG. 3. Facets of the cuprite crystals can be seen in the TEM image of FIG. 3. FIG. 4 shows a SEM image of a cross-section of the glass, after polishing with water. From FIG. 4, a preferential dissolution of a degradable phase (i.e., the phase-separated glassy regions enriched with phosphorus, boron and potassium shown in FIG. 3) in water can be seen. The Cu¹⁺ ions contained in the cuprite crystals that form the degradable phase are released by the dissolution of the degradable phase.

FIG. 6 shows an STEM image of the glasses made from the compositions described herein. FIG. 6 shows a three-phase morphology in which copper is present in a particulate form and wrapped by phosphate and distributed in a glass matrix. Because the phosphate is lightly soluble in water and hence it will be dissolved by water, exposing the Cu particles that will release active Cu species to function (killing viruses and bacteria).

Phase separation of the glass upon melting is shown in FIGS. 7A-7B and 8A-8C, which are EDX hypermaps of cross-section TEM images of samples lifted from bulk and surface areas. The same magnification was used to in both TEM images. FIGS. 7A-7B show the bulk and surface areas, respectively, of Example 30 immediately after melting at 1650° C. and annealing at 650° C. versus quenching in water from the 1650° C. melt temperature. FIG. 7A, which shows the quenched sample, is phase separated and includes cuprite crystals within a degradable phase. Accordingly, the phase separation and formation of crystals was not suppressed by quenching. Accordingly, FIG. 7A shows phase separation occurs at 1600° C. or in the melt. Specifically, FIG. 7A shows a durable phase as the darkest color, the lightest parts indicate the presence of copper and parts surrounding the lightest parts and having a slightly darker color represents phosphorus. FIGS. 8A-8B show SEM images of a fracture cross-section and a polished cross-section, respectively, of Example 30 following an additional heat treatment at 800° C. for 1 hour. The additional heat treatment appears to have ripened the microstructure. The size of largest cuprite crystals increased and the number of nanoscale bright contrast phases is significantly reduced when compared to samples prepared by a standard method, as shown in FIGS. 4 and 5. In some embodiments, the concentration of copper exceeds the solubility limit in the degradable phase and the copper precipitates out of the degradable phase. Accordingly, the antimicrobial glass has antimicrobial activity in the molten state and when cooled into the finished state, without any additional heat treatment (e.g., heat treatment in hydrogen at temperatures up to about 600° C.). The antimicrobial glass includes Cu¹⁺ and/or Cu⁰ in sufficient amounts and present in the degradable phase, that copper ions are leached out and provide antimicrobial efficacy.

The release of the Cu¹⁺ ions provides the antimicrobial activity, as demonstrated in the log reduction of Staphylococcus aureus under the EPA Test when the glass was tested as-received and after 1 day under the conditions listed in Table 4.

The antimicrobial performance of the glasses described herein was tested by forming a coupon or substrate article having dimensions of 2.5 cm×2.5 cm.

To test the antimicrobial activity of the examples, the EPA Test was utilized. In the examples described herein, Staphylococcus aureus (ATCC 6538) was cultured for 5 consecutive days before the testing was performed. Bacterial culture was mixed with serum (5% final concentration) and Triton X-100 (final concentration 0.01%). Each sample/carrier was inoculated with 20 μl of the bacterial suspension and allowed to dry (typically, for about 20 minutes to 40 minutes) at room temperature and 42% relative humidity prior to being exposed to bacterial for a 2 hour exposure period. After 2 hours of exposure, bacteria are washed from the carrier using neutralizer buffer and plated onto Tryptic soy agar plates. Twenty-four hours after incubation at 37° C., bacteria colony formation was examined and counted. Geometric mean and percent reduction were calculated based on the colony number from samples relative to glass carrier or appropriate paint control.

The articles according to one or more embodiments were formed as follows. The glass was ground into a powder and mixed with a commercially available carrier described as a clear gloss protective finish, available under the trademark Polycrylic® from Minwax Company. The copper loading (wt %/wt %) was either about 5%, 10% or 15% (calculated on the basis that the glass includes about 20 wt % Cu). The mixed carrier and glass powder was then brush coated onto Pyvek® paper that was backed with a polymer film, before being coated. The coated Pyvek® paper was cut into 2.5×2.5 cm coupons for the antimicrobial performance testing.

Where a thermoplastic polymer was utilized, the glass powder was compounded with a commercially available polymer, having the trademark Peralthane®, at a temperature in the range from between 195° C.-220° C. and a rate of 50 rpm. The loading of the glass was at about 60-80%. The resulting polymer and glass composite was made into 2.5×2.5 cm coupons by a hot press process.

In some examples, an epoxy resin was utilized. In such examples, about 3.0 g of a commercially available epoxy resin, Erisys GE22, was combined with about 1 g of a curing agent, Amicure PACM and 2 g of ethanol in a 20 mL vial, and mixed well. About 10 g of the powdered glass was added and mixed well. The resulting mixture was cured at room temperature for a few days and then the vial was broken to gel the combination, which was further dried at room temperature for one day and at 65° C. for several hours. This results in dried epoxy resin/glass composite.

The examples that were combined with an epoxy resin were also tested to determine the density or porosity of the composite. This included placing the example in water for 2 minutes and then removing the example. The mass difference before and after placement in the water was measured to demonstrate the porosity of the example.

Coupons made entirely of the glasses of Examples 4, 5, 6, 9, 10, 12, 13, 14 and 21 were tested under the EPA Test. In addition, a Comparative Substrate of pure copper metal was also tested under the EPA Test. FIG. 9 illustrates the antimicrobial performance of those glasses. Example 14 exhibited at least the same antimicrobial performance as the Comparative Substrate, with Examples 6, 12 and 13 exhibiting greater than 3 log reduction in Staphylococcus aureus.

Glass 56 was formed into particles having an average major dimension of about 1 μm or less. The particles were combined with a polymer carrier. The loading of the particles in the carrier was about 5%. The antimicrobial efficacy, as measured by the EPA test for S. aureus was evaluated immediately after the combination of the particles and the polymer carrier, one week after combination of the particles and the polymer carrier, one month after combination of the particles and the polymer carrier, and three months after combination of the particles and the polymer carrier. FIG. 10 is a graph showing the antimicrobial efficacy after each period of time. As shown in FIG. 10, the glass exhibits at least a 2 log reduction in S. aureus even at three months after being formed into particles and combined with a polymer carrier. In addition, the combination of the glass particles and the polymer carrier exhibited greater than 5 log reduction at one month after combination.

Glass 56 and a Comparative Glass (A) (including 10% by weight silver ion content diffused therein) were evaluated for antimicrobial activity with respect to Murine Norovirus and cytotoxicity, under the Modified JIS Z 2801 Test for Viruses. Antimicrobial activity control samples and cytotoxicity control samples of Glass 56 and Comparative Glass A were also prepared, as described per the Modified JIS Z 2801 Test for Viruses. Table 5 shows the input virus control and the antimicrobial activity control results, Table 6 shows the cytotoxicity control results, Table 7 shows the results of Comparative Glass A after a 2-hour exposure time to Murine Norovirus, Table 8 shows the results of Glass 56 after a 2-hour exposure time to Murine Norovirus, Table 9 shows the cytotoxicity of Comparative Glass A and Glass 56 on RAW 264.7 cell cultures, and Table 10 shows the non-virucidal level of the test virus as measured on the cytotoxicity control samples for Comparative Glass A and Glass 56.

TABLE 5 Input Virus Control and Antimicrobial Activity Control Results. Input Antimicrobial Activity Control Virus Replicate Replicate Replicate Dilution Control #1 #2 #3 Cell control 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10⁻¹ + + NT NT NT 10⁻² + + + + + + + + + + + + + + 10⁻³ + + + + + + + + + + + + + + 10⁻⁴ + + + + + + + + + + + + + + 10⁻⁵ + + + + + + + + + + + + + + 10⁻⁶ + + 0 + + + + + 0 + + + + + 10⁻⁷ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10⁻⁸ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 PFU₅₀/250 μL 10^(6.50) 10^(6.25) 10^(6.25) 10^(6.50) Mean PFU₅₀/250 μL NA 10^(6.33) (+) = positive for presence of test virus (0) = No test virus recovered and/or no cytotoxicity present (NA) = Not applicable (NT) = Not tested

TABLE 6 Cytotoxicity Control Results. Cytotoxicity Control (after 2 hour exposure time) Dilution Replicate #1 Replicate #2 Replicate #3 Cell control 0 0 0 0 0 0 0 0 0 0 0 0 10⁻² + + + + + + + + + + + + 10⁻³ + + + + + + + + + + + + 10⁻⁴ + + + + + + + + + + + + 10⁻⁵ + + + + + + + + + + + + 10⁻⁶ 0 0 0 0 0 0 + 0 0 + 0 0 10⁻⁷ 0 0 0 0 0 0 0 0 0 0 0 0 10⁻⁸ 0 0 0 0 0 0 0 0 0 0 0 0 PFU₅₀/250 μL 10^(5.5) 10^(5.75) 10^(5.75) Mean PFU₅₀/250 μL 10^(5.67) (+) = positive for presence of test virus (0) = No test virus recovered and/or no cytotoxicity present

TABLE 7 Results of Comparative Glass A after 2 hour exposure time to Murine Norovirus. Comparative Glass A-exposure to Murine Norovirus Dilution Replicate #1 Replicate #2 Replicate #3 Cell control 0 0 0 0 0 0 0 0 0 0 0 0 10⁻² + + + + + + + + + + + + 10⁻³ + + + + + + + + + + + + 10⁻⁴ + + + + + + + + + + + + 10⁻⁵ + + + + + + + + + + + + 10⁻⁶ 0 + + 0 + 0 0 + + + 0 0 10⁻⁷ 0 0 0 0 0 0 0 0 0 0 0 0 10⁻⁸ 0 0 0 0 0 0 0 0 0 0 0 0 PFU₅₀/250 μL 10^(6.00) 10^(6.00) 10^(6.00) Mean PFU₅₀/250 μL 10^(6.00) Mean % reduction (based on cytotoxicity No reduction control) Mean Log₁₀ Reduction (based on No reduction cytotoxicity control) Mean % reduction (based on antimicrobial 53.2% activity control) Mean Logic, Reduction (based on 0.33 Log₁₀ antimicrobial activity control) (+) = positive for presence of test virus (0) = No test virus recovered and/or no cytotoxicity present

TABLE 8 Results of Glass 56 after 2 hour exposure time to Murine Norovirus. Glass 56-exposure to Murine Norovirus Replicate Replicate Replicate Dilution #1 #2 #3 Cell control 0 0 0 0 0 0 0 0 0 0 0 0 10⁻² + + + + 0 0 0 0 0 0 0 0 10⁻³ + 0 + 0 0 0 0 0 0 0 0 0 10⁻⁴ 0 0 0 0 0 0 0 0 0 0 0 0 10⁻⁵ 0 0 0 0 0 0 0 0 0 0 0 0 10⁻⁶ 0 0 0 0 0 0 0 0 0 0 0 0 10⁻⁷ 0 0 0 0 0 0 0 0 0 0 0 0 10⁻⁸ 0 0 0 0 0 0 0 0 0 0 0 0 PFU₅₀/250 μL ≤10^(3.00) ≤10^(1.50) ≤10^(1.50) Mean PFU₅₀/250 μL ≤10^(2.00) Mean % reduction (based on ≥99.98% cytotoxicity control) Mean Logic, Reduction (based ≥3.67 Log₁₀ on cytotoxicity control) Mean % reduction (based on ≥99.995% antimicrobial activity control) Mean Logic, Reduction (based ≥4.33 Log₁₀ on antimicrobial activity control) (+) = positive for presence of test virus (0) = No test virus recovered and/or no cytotoxicity present

TABLE 9 Cytotoxicity of Control Comparative Glass A and Control Glass 56 on RAW 264.7 Cell Cultures. Cytotoxicity Control Dilution Comparative Glass A Glass 56 Cell control 0 0 0 0 10⁻² 0 0 0 0 10⁻³ 0 0 0 0 10⁻⁴ 0 0 0 0 10⁻⁵ 0 0 0 0 10⁻⁶ 0 0 0 0 10⁻⁷ 0 0 0 0 10⁻⁸ 0 0 0 0 TCD₅₀/250 μL ≤10^(1.50) ≤10^(1.50) (0) = No test virus recovered and/or no cytotoxicity present

TABLE 10 Non-virucidal Level of Test Substance (Neutralization Control). Antimicrobial Activity + Cytotoxicity Control Dilution Comparative Glass A Glass 56 Cell control 0 0 0 0 10⁻² + + + + 10⁻³ + + + + 10⁻⁴ + + + + 10⁻⁵ + + + + 10⁻⁸ + + + + 10⁻² + + + + 10⁻⁸ + + + + (+) = Positive for the presence of test virus after low titer stock virus added (neutralization control) (0) = No test virus recovered and/or no cytotoxicity present

Comparative Glass A exhibited a 0.33 log reduction in Murine Norovirus (or a 53.2% mean reduction), following a 2 hour exposure time at room temperature (20° C.) in a relative humidity of 42%, as compared to the antimicrobial activity control sample. Glass 56, however, exhibited a greater than 4.33 log reduction in Murine Norovirus (or 99.995% mean reduction or greater), following a 2 hour exposure time at room temperature (20° C.) in a relative humidity of 42%, as compared to the antimicrobial activity control sample.

Comparative Glass A did not demonstrate a mean reduction in viral titer of Murine Norovirus, following a 2 hour exposure time at room temperature (20° C.) in a relative humidity of 42%, in the presence of a 5% fetal bovine serum organic soil load, as compared to the cytotoxicity control sample. Glass 56, however, exhibited a greater than 3.67 mean log reduction in Murine Norovirus (or at least 99.98% or greater mean reduction), following a 2 hour exposure time at room temperature (20° C.) in a relative humidity of 42%, in the presence of a 5% fetal bovine serum organic soil load, as compared to the cytotoxicity control sample.

The results shown in Table 10 indicate that each test sample was neutralized at a PFU₅₀/250 μL of 1.5 log₁₀.

Examples 12, 13 and 14 were formed into a powder and mixed with Polycrylic® at different loadings, based on Cu₂O content. The mixtures were then coated onto Pyvek® paper (that was backed with a plastic film before coated) through a brushing process and cured for 1 week. The coated paper was cut into coupons for testing under the EPA Test. FIGS. 11 and 12 illustrate the results. FIG. 11 shows the antimicrobial performance of the coupons, having different copper loadings. FIG. 12 illustrates the antimicrobial performance of the composites with 15% Cu₂O.

Example 12 was ground into a powder and mixed with Pearlthane® polyurethane to provide a composite having different amounts of glass (by weight percent). The powdered glass and polyurethane were mixed at 195-220° C. for several minutes. The resulting combination was made into a 2.5 cm×2.5 cm coupon using melt processing, and evaluated for antimicrobial performance using the EPA Test. The results are provided in FIG. 13.

Injection molded articles were formed to evaluate antimicrobial activity when the surface is typically covered by a thin layer of matrix polymer. In such articles, the matrix polymer is typically hydrophobic and may affect antimicrobial performance. As shown in FIG. 14, surface treatment can improve antimicrobial performance. To prepare the injection molded samples, Example 12 was ground into a powder and mixed with Pearlthane® polyurethane to provide an injection moldable composite having 60 wt % glass. The composite was injection molded in a petri dish as shown in FIG. 14 to provide four injection molded samples (Samples A-D) that were evaluated for antimicrobial performance using the EPA Test. Sample A was not subjected to surface treatment. Sample B was sanded to remove about 10 mg of top surface of the sample. Samples C and D were subjected to plasma treatment using 100 W of power and pressure of 2 torr for 5 minutes using two different gases, as shown in Table 11. FIG. 15 shows the log reduction of Samples A-D.

TABLE 11 Plasma Treatment condition for Samples C and D. Material Time, min Power, W Pressure, torr Gas Sample C 5 100 2 air Sample D 5 100 2 N₂/H₂ (94/6% by volume)

As discussed herein, thermoplastic polymers may be utilized to form the articles described herein through melt compounding processes. Articles using a thermoplastic polymer may also be formed by in situ polymerization and then into an article by a casting process. An epoxy resin (which is a thermosetting polymer) was used to demonstrate the concept. The epoxy resin was made from Erisys GE22 and Amicure PACM, which were mixed well in presence of alcohol. Example 12 was ground into a powder and added to the mixture according to Table 12, resulting in a paste-like material that was cast into a mold. In this example, a glass vial was used as a mold. The combination of the epoxy resin and ground glass was then cured at room temperature for a few days. The mold was then removed and the resulting article was dried at room temperature for one day and at 65° C. for a few hours.

Table 12: Composition for making an article with epoxy resin and ground glass from Example 12.

TABLE 12 Materials Weight, parts Weight, parts Weight, parts Erisys GE22 1 1 3 Amicure PACM 0.3 0.3 1 Ethanol 6 5 2 Example 12 15 10 10

Depending on the loading of the glass in the article, the resulting article may be porous or dense. The porosity increases with the increase of glass loading as seen in Table 13, in which the water uptake by the articles was measured after soaking the article in water for 2 minutes. Different articles were made from the same epoxy as used in Table 12 was combined with different amounts of ground glass from Example 12. The article was made using gel casting.

Table 13: water uptake of articles using epoxy resin and different loadings of ground glass from Example 12.

TABLE 13 Example 12 glass loading Water uptake in 2 (wt %/wt %) minutes, % 71 0.5 88 5.9 92 20.7

It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the invention. 

What is claimed is:
 1. A method comprising: forming a glass from a batch comprising (in mol %): 44 to 66 SiO₂; 18 to 37 copper-containing oxide; and 5 to 13 R₂O, wherein R is one or more of K and Na; and annealing the glass at a temperature of 600° C. to 700° C.; wherein, phase separation within the glass occurred during the step of forming the glass without any additional heat treatment; wherein, the phase separation resulted in (i) a glassy matrix phase, (ii) a degradable phase, and (iii) a cuprite crystalline phase disposed within the degradable phase; wherein, the glassy matrix phase is enriched in silicon relative to the degradable phase; and wherein, the cuprite crystalline phase has an average major dimension, before the glass is subjected to a step of forming the glass into particles, of about 5 micrometers (μm) or less.
 2. The method of claim 1, wherein the batch composition further comprises (in mol %): Al₂O₃: 3 to 8; and P₂O₅: 2 to 8; and the batch composition is substantially free of B₂O₃.
 3. The method of claim 1, wherein the batch composition further comprises (in mol %): B₂O₃: 3 to 13; and P₂O₅: 4 to 12; and the batch composition is substantially free of Al₂O₃.
 4. The method of claim 1, wherein the batch composition further comprises (in mol %) Al₂O₃: 3 to 8; B₂O₃: 8 to 12; and P₂O₅: 2 to
 8. 5. The method of claim 1, further comprising: forming the glass into particles having an average major dimension of about 0.1 μm to about 1 μm; combining the particles of the glass with a carrier thus forming a composite; molding the composite into an article; and sanding a top surface of the article or subjecting the top surface of the article to a plasma treatment; wherein, the carrier comprises a polymer, and the polymer comprises polyurethane or epoxy resin.
 6. The method of claim 1, further comprising forming the glass into particles having an average major dimension of about 0.1 μm to about 1 μm; and combining the particles of the glass with a carrier thus forming a composite; wherein, the carrier comprises an acrylic latex paint. 